X-Git-Url: https://git.lyx.org/gitweb/?a=blobdiff_plain;f=src%2FBuffer.cpp;h=38d236964af0393b0b4b922d8257fb3e03bf23b2;hb=1511516ef769cb3a11546a78cea6abd41cb91ffe;hp=bf83f9f816711ef937ad992ab62f2e756cc15730;hpb=3fd2398a28c8d2c85d1bb2c33c6ca15bfc398b54;p=lyx.git

diff --git a/src/Buffer.cpp b/src/Buffer.cpp
index bf83f9f816..38d236964a 100644
--- a/src/Buffer.cpp
+++ b/src/Buffer.cpp
@@ -14,7 +14,6 @@
 #include "Buffer.h"
 
 #include "Author.h"
-#include "LayoutFile.h"
 #include "BiblioInfo.h"
 #include "BranchList.h"
 #include "buffer_funcs.h"
@@ -22,6 +21,7 @@
 #include "BufferParams.h"
 #include "Bullet.h"
 #include "Chktex.h"
+#include "ColorSet.h"
 #include "Converter.h"
 #include "Counters.h"
 #include "Cursor.h"
@@ -46,17 +46,18 @@
 #include "LyX.h"
 #include "LyXRC.h"
 #include "LyXVC.h"
-#include "output_docbook.h"
 #include "output.h"
 #include "output_latex.h"
-#include "output_xhtml.h"
+#include "output_docbook.h"
 #include "output_plaintext.h"
+#include "output_xhtml.h"
 #include "Paragraph.h"
 #include "ParagraphParameters.h"
 #include "ParIterator.h"
 #include "PDFOptions.h"
+#include "Session.h"
 #include "SpellChecker.h"
-#include "sgml.h"
+#include "xml.h"
 #include "texstream.h"
 #include "TexRow.h"
 #include "Text.h"
@@ -66,21 +67,19 @@
 #include "VCBackend.h"
 #include "version.h"
 #include "WordLangTuple.h"
-#include "WordList.h"
 
-#include "insets/InsetBibtex.h"
 #include "insets/InsetBranch.h"
 #include "insets/InsetInclude.h"
-#include "insets/InsetTabular.h"
 #include "insets/InsetText.h"
 
 #include "mathed/InsetMathHull.h"
 #include "mathed/MacroTable.h"
-#include "mathed/MathMacroTemplate.h"
+#include "mathed/InsetMathMacroTemplate.h"
 #include "mathed/MathSupport.h"
 
 #include "graphics/PreviewLoader.h"
 
+#include "frontends/Application.h"
 #include "frontends/alert.h"
 #include "frontends/Delegates.h"
 #include "frontends/WorkAreaManager.h"
@@ -90,14 +89,13 @@
 #include "support/debug.h"
 #include "support/docstring_list.h"
 #include "support/ExceptionMessage.h"
+#include "support/FileMonitor.h"
 #include "support/FileName.h"
 #include "support/FileNameList.h"
 #include "support/filetools.h"
-#include "support/ForkedCalls.h"
 #include "support/gettext.h"
 #include "support/gzstream.h"
 #include "support/lstrings.h"
-#include "support/lyxalgo.h"
 #include "support/mutex.h"
 #include "support/os.h"
 #include "support/Package.h"
@@ -107,8 +105,6 @@
 #include "support/textutils.h"
 #include "support/types.h"
 
-#include "support/bind.h"
-
 #include <algorithm>
 #include <fstream>
 #include <iomanip>
@@ -132,13 +128,29 @@ namespace {
 int const LYX_FORMAT = LYX_FORMAT_LYX;
 
 typedef map<string, bool> DepClean;
-typedef map<docstring, pair<InsetLabel const *, Buffer::References> > RefCache;
 
-} // namespace anon
+// Information about labels and their associated refs
+struct LabelInfo {
+	/// label string
+	docstring label;
+	/// label inset
+	InsetLabel const * inset;
+	/// associated references cache
+	Buffer::References references;
+	/// whether this label is active (i.e., not deleted)
+	bool active;
+};
+
+typedef vector<LabelInfo> LabelCache;
 
+typedef map<docstring, Buffer::References> RefCache;
 
 // A storehouse for the cloned buffers.
-list<CloneList *> cloned_buffers;
+typedef list<CloneList_ptr> CloneStore;
+CloneStore cloned_buffers;
+
+} // namespace
+
 
 
 class Buffer::Impl
@@ -169,7 +181,7 @@ public:
 	/** If we have branches that use the file suffix
 	    feature, return the file name with suffix appended.
 	*/
-	support::FileName exportFileName() const;
+	FileName exportFileName() const;
 
 	Buffer * owner_;
 
@@ -181,40 +193,9 @@ public:
 	/// need to regenerate .tex?
 	DepClean dep_clean;
 
-	/// is save needed?
-	mutable bool lyx_clean;
-
-	/// is autosave needed?
-	mutable bool bak_clean;
-
-	/// is this an unnamed file (New...)?
-	bool unnamed;
-
-	/// is this an internal bufffer?
-	bool internal_buffer;
-
-	/// buffer is r/o
-	bool read_only;
-
 	/// name of the file the buffer is associated with.
 	FileName filename;
 
-	/** Set to true only when the file is fully loaded.
-	 *  Used to prevent the premature generation of previews
-	 *  and by the citation inset.
-	 */
-	bool file_fully_loaded;
-
-	/// original format of loaded file
-	int file_format;
-
-	/// if the file was originally loaded from an older format, do
-	/// we need to back it up still?
-	bool need_format_backup;
-
-	/// Ignore the parent (e.g. when exporting a child standalone)?
-	bool ignore_parent;
-
 	///
 	mutable TocBackend toc_backend;
 
@@ -231,13 +212,11 @@ public:
 	/// map from the macro name to the position map,
 	/// which maps the macro definition position to the scope and the MacroData.
 	NamePositionScopeMacroMap macros;
-	/// This seem to change the way Buffer::getMacro() works
-	mutable bool macro_lock;
 
 	/// positions of child buffers in the buffer
 	typedef map<Buffer const * const, DocIterator> BufferPositionMap;
 	struct ScopeBuffer {
-		ScopeBuffer() : buffer(0) {}
+		ScopeBuffer() : buffer(nullptr) {}
 		ScopeBuffer(DocIterator const & s, Buffer const * b)
 			: scope(s), buffer(b) {}
 		DocIterator scope;
@@ -262,9 +241,8 @@ public:
 	/// Container for all sort of Buffer dependant errors.
 	map<string, ErrorList> errorLists;
 
-	/// timestamp and checksum used to test if the file has been externally
-	/// modified. (Used to properly enable 'File->Revert to saved', bug 4114).
-	time_t timestamp_;
+	/// checksum used to test if the file has been externally modified.  Used to
+	/// double check whether the file had been externally modified when saving.
 	unsigned long checksum_;
 
 	///
@@ -277,7 +255,7 @@ public:
 
 	/// A cache for the bibfiles (including bibfiles of loaded child
 	/// documents), needed for appropriate update of natbib labels.
-	mutable support::FileNameList bibfiles_cache_;
+	mutable docstring_list bibfiles_cache_;
 
 	// FIXME The caching mechanism could be improved. At present, we have a
 	// cache for each Buffer, that caches all the bibliography info for that
@@ -285,27 +263,19 @@ public:
 	// file, and then to construct the Buffer's bibinfo from that.
 	/// A cache for bibliography info
 	mutable BiblioInfo bibinfo_;
-	/// whether the bibinfo cache is valid
-	mutable bool bibinfo_cache_valid_;
-	/// whether the bibfile cache is valid
-	mutable bool bibfile_cache_valid_;
 	/// Cache of timestamps of .bib files
 	map<FileName, time_t> bibfile_status_;
-	/// Indicates whether the bibinfo has changed since the last time
-	/// we ran updateBuffer(), i.e., whether citation labels may need
-	/// to be updated.
-	mutable bool cite_labels_valid_;
 
 	/// These two hold the file name and format, written to by
 	/// Buffer::preview and read from by LFUN_BUFFER_VIEW_CACHE.
 	FileName preview_file_;
 	string preview_format_;
-	/// If there was an error when previewing, on the next preview we do
-	/// a fresh compile (e.g. in case the user installed a package that
-	/// was missing).
-	bool preview_error_;
 
+	/// Cache the references associated to a label and their positions
+	/// in the buffer.
 	mutable RefCache ref_cache_;
+	/// Cache the label insets and their activity status.
+	mutable LabelCache label_cache_;
 
 	/// our Text that should be wrapped in an InsetText
 	InsetText * inset;
@@ -313,6 +283,86 @@ public:
 	///
 	PreviewLoader * preview_loader_;
 
+	/// If non zero, this buffer is a clone of existing buffer \p cloned_buffer_
+	/// This one is useful for preview detached in a thread.
+	Buffer const * cloned_buffer_;
+	///
+	CloneList_ptr clone_list_;
+
+	///
+	std::list<Buffer const *> include_list_;
+private:
+	/// So we can force access via the accessors.
+	mutable Buffer const * parent_buffer;
+
+	FileMonitorPtr file_monitor_;
+
+/// ints and bools are all listed last so as to avoid alignment issues
+public:
+	/// original format of loaded file
+	int file_format;
+
+	/// are we in the process of exporting this buffer?
+	mutable bool doing_export;
+
+	/// If there was an error when previewing, on the next preview we do
+	/// a fresh compile (e.g. in case the user installed a package that
+	/// was missing).
+	bool require_fresh_start_;
+
+	/// Indicates whether the bibinfo has changed since the last time
+	/// we ran updateBuffer(), i.e., whether citation labels may need
+	/// to be updated.
+	mutable bool cite_labels_valid_;
+	/// Do we have a bibliography environment?
+	mutable bool have_bibitems_;
+
+	/// is save needed?
+	mutable bool lyx_clean;
+
+	/// is autosave needed?
+	mutable bool bak_clean;
+
+	/// is this an unnamed file (New...)?
+	bool unnamed;
+
+	/// is this an internal bufffer?
+	bool internal_buffer;
+
+	/// buffer is r/o
+	bool read_only;
+
+	/** Set to true only when the file is fully loaded.
+	 *  Used to prevent the premature generation of previews
+	 *  and by the citation inset.
+	 */
+	bool file_fully_loaded;
+
+	/// if the file was originally loaded from an older format, do
+	/// we need to back it up still?
+	bool need_format_backup;
+
+	/// Ignore the parent (e.g. when exporting a child standalone)?
+	bool ignore_parent;
+
+	/// This seem to change the way Buffer::getMacro() works
+	mutable bool macro_lock;
+
+	/// has been externally modified? Can be reset by the user.
+	mutable bool externally_modified_;
+
+	/// whether the bibinfo cache is valid
+	mutable bool bibinfo_cache_valid_;
+
+	///
+	mutable bool need_update;
+
+private:
+	int word_count_;
+	int char_count_;
+	int blank_count_;
+
+public:
 	/// This is here to force the test to be done whenever parent_buffer
 	/// is accessed.
 	Buffer const * parent() const
@@ -320,7 +370,7 @@ public:
 		// ignore_parent temporarily "orphans" a buffer
 		// (e.g. if a child is compiled standalone)
 		if (ignore_parent)
-			return 0;
+			return nullptr;
 		// if parent_buffer is not loaded, then it has been unloaded,
 		// which means that parent_buffer is an invalid pointer. So we
 		// set it to null in that case.
@@ -328,7 +378,7 @@ public:
 		// they will always be regarded as unloaded. in that case, we hope
 		// for the best.
 		if (!cloned_buffer_ && !theBufferList().isLoaded(parent_buffer))
-			parent_buffer = 0;
+			parent_buffer = nullptr;
 		return parent_buffer;
 	}
 
@@ -341,20 +391,10 @@ public:
 		if (!cloned_buffer_ && parent_buffer && pb)
 			LYXERR0("Warning: a buffer should not have two parents!");
 		parent_buffer = pb;
-		if (!cloned_buffer_ && parent_buffer) {
-			parent_buffer->invalidateBibfileCache();
+		if (!cloned_buffer_ && parent_buffer)
 			parent_buffer->invalidateBibinfoCache();
-		}
 	}
 
-	/// If non zero, this buffer is a clone of existing buffer \p cloned_buffer_
-	/// This one is useful for preview detached in a thread.
-	Buffer const * cloned_buffer_;
-	///
-	CloneList * clone_list_;
-	/// are we in the process of exporting this buffer?
-	mutable bool doing_export;
-
 	/// compute statistics
 	/// \p from initial position
 	/// \p to points to the end position
@@ -371,18 +411,17 @@ public:
 		+ (with_blanks ? blank_count_ : 0);
 	}
 
-	// does the buffer contain tracked changes? (if so, we automatically
-	// display the review toolbar, for instance)
-	mutable bool tracked_changes_present_;
+	// Make sure the file monitor monitors the good file.
+	void refreshFileMonitor();
 
-private:
-	/// So we can force access via the accessors.
-	mutable Buffer const * parent_buffer;
-
-	int word_count_;
-	int char_count_;
-	int blank_count_;
+	/// Notify or clear of external modification
+	void fileExternallyModified(bool exists);
 
+	///Binding LaTeX lines with buffer positions.
+	//Common routine for LaTeX and Reference errors listing.
+        void traverseErrors(TeXErrors::Errors::const_iterator err,
+		TeXErrors::Errors::const_iterator end,
+		ErrorList & errorList) const;
 };
 
 
@@ -415,19 +454,26 @@ static FileName createBufferTmpDir()
 
 Buffer::Impl::Impl(Buffer * owner, FileName const & file, bool readonly_,
 	Buffer const * cloned_buffer)
-	: owner_(owner), lyx_clean(true), bak_clean(true), unnamed(false),
-	  internal_buffer(false), read_only(readonly_), filename(file),
-	  file_fully_loaded(false), file_format(LYX_FORMAT), need_format_backup(false),
-	  ignore_parent(false),  toc_backend(owner), macro_lock(false), timestamp_(0),
-	  checksum_(0), wa_(0),  gui_(0), undo_(*owner), bibinfo_cache_valid_(false),
-	  bibfile_cache_valid_(false), cite_labels_valid_(false), inset(0),
-	  preview_loader_(0), cloned_buffer_(cloned_buffer), clone_list_(0),
-	  doing_export(false), parent_buffer(0),
-	  word_count_(0), char_count_(0), blank_count_(0)
-{
+	: owner_(owner), filename(file), toc_backend(owner), checksum_(0),
+	  wa_(nullptr),  gui_(nullptr), undo_(*owner), inset(nullptr),
+	  preview_loader_(nullptr), cloned_buffer_(cloned_buffer),
+	  clone_list_(nullptr), parent_buffer(nullptr), file_format(LYX_FORMAT),
+	  doing_export(false), require_fresh_start_(false), cite_labels_valid_(false),
+	  have_bibitems_(false), lyx_clean(true), bak_clean(true), unnamed(false),
+	  internal_buffer(false), read_only(readonly_), file_fully_loaded(false),
+	  need_format_backup(false), ignore_parent(false), macro_lock(false),
+	  externally_modified_(false), bibinfo_cache_valid_(false),
+	  need_update(false), word_count_(0), char_count_(0), blank_count_(0)
+{
+	refreshFileMonitor();
 	if (!cloned_buffer_) {
 		temppath = createBufferTmpDir();
 		lyxvc.setBuffer(owner_);
+		Language const * inplang = theApp() ?
+					languages.getFromCode(theApp()->inputLanguageCode())
+				      : nullptr;
+		if (inplang)
+			params.language = inplang;
 		if (use_gui)
 			wa_ = new frontend::WorkAreaManager;
 		return;
@@ -438,16 +484,15 @@ Buffer::Impl::Impl(Buffer * owner, FileName const & file, bool readonly_,
 	bibfiles_cache_ = cloned_buffer_->d->bibfiles_cache_;
 	bibinfo_ = cloned_buffer_->d->bibinfo_;
 	bibinfo_cache_valid_ = cloned_buffer_->d->bibinfo_cache_valid_;
-	bibfile_cache_valid_ = cloned_buffer_->d->bibfile_cache_valid_;
 	bibfile_status_ = cloned_buffer_->d->bibfile_status_;
 	cite_labels_valid_ = cloned_buffer_->d->cite_labels_valid_;
+	have_bibitems_ = cloned_buffer_->d->have_bibitems_;
 	unnamed = cloned_buffer_->d->unnamed;
 	internal_buffer = cloned_buffer_->d->internal_buffer;
 	layout_position = cloned_buffer_->d->layout_position;
 	preview_file_ = cloned_buffer_->d->preview_file_;
 	preview_format_ = cloned_buffer_->d->preview_format_;
-	preview_error_ = cloned_buffer_->d->preview_error_;
-	tracked_changes_present_ = cloned_buffer_->d->tracked_changes_present_;
+	require_fresh_start_ = cloned_buffer_->d->require_fresh_start_;
 }
 
 
@@ -477,7 +522,7 @@ Buffer::~Buffer()
 	// saved properly, before it goes into the void.
 
 	// GuiView already destroyed
-	d->gui_ = 0;
+	d->gui_ = nullptr;
 
 	if (isInternal()) {
 		// No need to do additional cleanups for internal buffer.
@@ -490,12 +535,10 @@ Buffer::~Buffer()
 		// ourselves as a child.
 		d->clone_list_->erase(this);
 		// loop over children
-		Impl::BufferPositionMap::iterator it = d->children_positions.begin();
-		Impl::BufferPositionMap::iterator end = d->children_positions.end();
-		for (; it != end; ++it) {
-			Buffer * child = const_cast<Buffer *>(it->first);
-				if (d->clone_list_->erase(child))
-					delete child;
+		for (auto const & p : d->children_positions) {
+			Buffer * child = const_cast<Buffer *>(p.first);
+			if (d->clone_list_->erase(child))
+				delete child;
 		}
 		// if we're the master buffer, then we should get rid of the list
 		// of clones
@@ -504,14 +547,15 @@ Buffer::~Buffer()
 			// children still has a reference to this list. But we will try to
 			// continue, rather than shut down.
 			LATTEST(d->clone_list_->empty());
-			list<CloneList *>::iterator it =
+			// The clone list itself is empty, but it's still referenced in our list
+			// of clones. So let's find it and remove it.
+			CloneStore::iterator it =
 				find(cloned_buffers.begin(), cloned_buffers.end(), d->clone_list_);
 			if (it == cloned_buffers.end()) {
 				// We will leak in this case, but it is safe to continue.
 				LATTEST(false);
 			} else
 				cloned_buffers.erase(it);
-			delete d->clone_list_;
 		}
 		// FIXME Do we really need to do this right before we delete d?
 		// clear references to children in macro tables
@@ -519,21 +563,23 @@ Buffer::~Buffer()
 		d->position_to_children.clear();
 	} else {
 		// loop over children
-		Impl::BufferPositionMap::iterator it = d->children_positions.begin();
-		Impl::BufferPositionMap::iterator end = d->children_positions.end();
-		for (; it != end; ++it) {
-			Buffer * child = const_cast<Buffer *>(it->first);
-			if (theBufferList().isLoaded(child)) { 
-			 if (theBufferList().isOthersChild(this, child))
-				 child->setParent(0);
-			 else
-				theBufferList().release(child);
+		for (auto const & p : d->children_positions) {
+			Buffer * child = const_cast<Buffer *>(p.first);
+			if (theBufferList().isLoaded(child)) {
+				if (theBufferList().isOthersChild(this, child))
+					child->setParent(nullptr);
+				else
+					theBufferList().release(child);
 			}
 		}
 
 		if (!isClean()) {
 			docstring msg = _("LyX attempted to close a document that had unsaved changes!\n");
-			msg += emergencyWrite();
+			try {
+				msg += emergencyWrite();
+			} catch (...) {
+				msg += "  " + _("Save failed! Document is lost.");
+			}
 			Alert::warning(_("Attempting to close changed document!"), msg);
 		}
 
@@ -553,24 +599,24 @@ Buffer::~Buffer()
 }
 
 
-Buffer * Buffer::cloneFromMaster() const
+Buffer * Buffer::cloneWithChildren() const
 {
 	BufferMap bufmap;
-	cloned_buffers.push_back(new CloneList);
-	CloneList * clones = cloned_buffers.back();
+	cloned_buffers.emplace_back(new CloneList);
+	CloneList_ptr clones = cloned_buffers.back();
 
-	masterBuffer()->cloneWithChildren(bufmap, clones);
+	cloneWithChildren(bufmap, clones);
 
 	// make sure we got cloned
 	BufferMap::const_iterator bit = bufmap.find(this);
-	LASSERT(bit != bufmap.end(), return 0);
+	LASSERT(bit != bufmap.end(), return nullptr);
 	Buffer * cloned_buffer = bit->second;
 
 	return cloned_buffer;
 }
 
 
-void Buffer::cloneWithChildren(BufferMap & bufmap, CloneList * clones) const
+void Buffer::cloneWithChildren(BufferMap & bufmap, CloneList_ptr clones) const
 {
 	// have we already been cloned?
 	if (bufmap.find(this) != bufmap.end())
@@ -581,10 +627,9 @@ void Buffer::cloneWithChildren(BufferMap & bufmap, CloneList * clones) const
 	// The clone needs its own DocumentClass, since running updateBuffer() will
 	// modify it, and we would otherwise be sharing it with the original Buffer.
 	buffer_clone->params().makeDocumentClass(true);
-	ErrorList el;
 	cap::switchBetweenClasses(
 			params().documentClassPtr(), buffer_clone->params().documentClassPtr(),
-			static_cast<InsetText &>(buffer_clone->inset()), el);
+			static_cast<InsetText &>(buffer_clone->inset()));
 
 	bufmap[this] = buffer_clone;
 	clones->insert(buffer_clone);
@@ -596,12 +641,10 @@ void Buffer::cloneWithChildren(BufferMap & bufmap, CloneList * clones) const
 	// math macro caches need to be rethought and simplified.
 	// I am not sure wether we should handle Buffer cloning here or in BufferList.
 	// Right now BufferList knows nothing about buffer clones.
-	Impl::PositionScopeBufferMap::iterator it = d->position_to_children.begin();
-	Impl::PositionScopeBufferMap::iterator end = d->position_to_children.end();
-	for (; it != end; ++it) {
-		DocIterator dit = it->first.clone(buffer_clone);
+	for (auto const & p : d->position_to_children) {
+		DocIterator dit = p.first.clone(buffer_clone);
 		dit.setBuffer(buffer_clone);
-		Buffer * child = const_cast<Buffer *>(it->second.buffer);
+		Buffer * child = const_cast<Buffer *>(p.second.buffer);
 
 		child->cloneWithChildren(bufmap, clones);
 		BufferMap::iterator const bit = bufmap.find(child);
@@ -617,22 +660,20 @@ void Buffer::cloneWithChildren(BufferMap & bufmap, CloneList * clones) const
 		buffer_clone->setChild(dit, child_clone);
 	}
 	buffer_clone->d->macro_lock = false;
-	return;
 }
 
 
 Buffer * Buffer::cloneBufferOnly() const {
-	cloned_buffers.push_back(new CloneList);
-	CloneList * clones = cloned_buffers.back();
+	cloned_buffers.emplace_back(new CloneList);
+	CloneList_ptr clones = cloned_buffers.back();
 	Buffer * buffer_clone = new Buffer(fileName().absFileName(), false, this);
 
 	// The clone needs its own DocumentClass, since running updateBuffer() will
 	// modify it, and we would otherwise be sharing it with the original Buffer.
 	buffer_clone->params().makeDocumentClass(true);
-	ErrorList el;
 	cap::switchBetweenClasses(
 			params().documentClassPtr(), buffer_clone->params().documentClassPtr(),
-			static_cast<InsetText &>(buffer_clone->inset()), el);
+			static_cast<InsetText &>(buffer_clone->inset()));
 
 	clones->insert(buffer_clone);
 	buffer_clone->d->clone_list_ = clones;
@@ -694,10 +735,8 @@ BufferParams const & Buffer::masterParams() const
 
 	BufferParams & mparams = const_cast<Buffer *>(masterBuffer())->params();
 	// Copy child authors to the params. We need those pointers.
-	AuthorList const & child_authors = params().authors();
-	AuthorList::Authors::const_iterator it = child_authors.begin();
-	for (; it != child_authors.end(); ++it)
-		mparams.authors().record(*it);
+	for (Author const & a : params().authors())
+		mparams.authors().record(a);
 	return mparams;
 }
 
@@ -705,7 +744,7 @@ BufferParams const & Buffer::masterParams() const
 double Buffer::fontScalingFactor() const
 {
 	return isExporting() ? 75.0 * params().html_math_img_scale
-		: 0.01 * lyxrc.dpi * lyxrc.zoom * lyxrc.preview_scale_factor * params().display_pixel_ratio;
+		: 0.01 * lyxrc.dpi * lyxrc.currentZoom * lyxrc.preview_scale_factor * params().display_pixel_ratio;
 }
 
 
@@ -763,6 +802,12 @@ Undo & Buffer::undo()
 }
 
 
+Undo const & Buffer::undo() const
+{
+	return d->undo_;
+}
+
+
 void Buffer::setChild(DocIterator const & dit, Buffer * child)
 {
 	d->children_positions[child] = dit;
@@ -785,10 +830,9 @@ FileName Buffer::Impl::exportFileName() const
 	if (branch_suffix.empty())
 		return filename;
 
-	string const name = filename.onlyFileNameWithoutExt()
-		+ to_utf8(branch_suffix);
+	string const name = addExtension(filename.onlyFileNameWithoutExt()
+			+ to_utf8(branch_suffix), filename.extension());
 	FileName res(filename.onlyPath().absFileName() + "/" + name);
-	res.changeExtension(filename.extension());
 
 	return res;
 }
@@ -814,7 +858,7 @@ string Buffer::logName(LogType * type) const
 	FileName const bname(
 		addName(path, onlyFileName(
 			changeExtension(filename,
-					formats.extension(params().bufferFormat()) + ".out"))));
+					theFormats().extension(params().bufferFormat()) + ".out"))));
 
 	// Also consider the master buffer log file
 	FileName masterfname = fname;
@@ -862,6 +906,7 @@ void Buffer::setFileName(FileName const & fname)
 {
 	bool const changed = fname != d->filename;
 	d->filename = fname;
+	d->refreshFileMonitor();
 	if (changed)
 		lyxvc().file_found_hook(fname);
 	setReadonly(d->filename.isReadOnly());
@@ -882,6 +927,7 @@ int Buffer::readHeader(Lexer & lex)
 	params().options.erase();
 	params().master.erase();
 	params().float_placement.erase();
+	params().float_alignment.erase();
 	params().paperwidth.erase();
 	params().paperheight.erase();
 	params().leftmargin.erase();
@@ -892,25 +938,37 @@ int Buffer::readHeader(Lexer & lex)
 	params().headsep.erase();
 	params().footskip.erase();
 	params().columnsep.erase();
+	params().font_roman_opts.erase();
+	params().font_sans_opts.erase();
+	params().font_typewriter_opts.erase();
 	params().fonts_cjk.erase();
 	params().listings_params.clear();
 	params().clearLayoutModules();
 	params().clearRemovedModules();
 	params().clearIncludedChildren();
 	params().pdfoptions().clear();
+	params().document_metadata.clear();
 	params().indiceslist().clear();
 	params().backgroundcolor = lyx::rgbFromHexName("#ffffff");
 	params().isbackgroundcolor = false;
 	params().fontcolor = RGBColor(0, 0, 0);
 	params().isfontcolor = false;
 	params().notefontcolor = RGBColor(0xCC, 0xCC, 0xCC);
+	params().isnotefontcolor = false;
 	params().boxbgcolor = RGBColor(0xFF, 0, 0);
+	params().isboxbgcolor = false;
 	params().html_latex_start.clear();
 	params().html_latex_end.clear();
 	params().html_math_img_scale = 1.0;
 	params().output_sync_macro.erase();
-	params().setLocalLayout(string(), false);
-	params().setLocalLayout(string(), true);
+	params().setLocalLayout(docstring(), false);
+	params().setLocalLayout(docstring(), true);
+	params().biblio_opts.erase();
+	params().biblatex_bibstyle.erase();
+	params().biblatex_citestyle.erase();
+	params().multibib.erase();
+	params().lineno_opts.clear();
+	params().spellignore().clear();
 
 	for (int i = 0; i < 4; ++i) {
 		params().user_defined_bullet(i) = ITEMIZE_DEFAULTS[i];
@@ -939,7 +997,7 @@ int Buffer::readHeader(Lexer & lex)
 				      << token << '\'');
 
 		string const result =
-			params().readToken(lex, token, d->filename.onlyPath());
+			params().readToken(lex, token, d->filename);
 		if (!result.empty()) {
 			if (token == "\\textclass") {
 				d->layout_position = result;
@@ -949,18 +1007,18 @@ int Buffer::readHeader(Lexer & lex)
 									"%1$s %2$s\n"),
 							 from_utf8(token),
 							 lex.getDocString());
-				errorList.push_back(ErrorItem(_("Document header error"),
-					s, -1, 0, 0));
+				errorList.push_back(ErrorItem(_("Document header error"), s));
 			}
 		}
 	}
 	if (begin_header_line) {
 		docstring const s = _("\\begin_header is missing");
-		errorList.push_back(ErrorItem(_("Document header error"),
-			s, -1, 0, 0));
+		errorList.push_back(ErrorItem(_("Document header error"), s));
 	}
 
-	params().makeDocumentClass();
+	params().shell_escape = theSession().shellescapeFiles().find(absFileName());
+
+	params().makeDocumentClass(isClone(), isInternal());
 
 	return unknown_tokens;
 }
@@ -979,27 +1037,19 @@ bool Buffer::readDocument(Lexer & lex)
 
 	if (!lex.checkFor("\\begin_document")) {
 		docstring const s = _("\\begin_document is missing");
-		errorList.push_back(ErrorItem(_("Document header error"),
-			s, -1, 0, 0));
+		errorList.push_back(ErrorItem(_("Document header error"), s));
 	}
 
 	readHeader(lex);
 
 	if (params().output_changes) {
-		bool dvipost    = LaTeXFeatures::isAvailable("dvipost");
 		bool xcolorulem = LaTeXFeatures::isAvailable("ulem") &&
 				  LaTeXFeatures::isAvailable("xcolor");
 
-		if (!dvipost && !xcolorulem) {
+		if (!xcolorulem) {
 			Alert::warning(_("Changes not shown in LaTeX output"),
 				       _("Changes will not be highlighted in LaTeX output, "
-					 "because neither dvipost nor xcolor/ulem are installed.\n"
-					 "Please install these packages or redefine "
-					 "\\lyxadded and \\lyxdeleted in the LaTeX preamble."));
-		} else if (!xcolorulem) {
-			Alert::warning(_("Changes not shown in LaTeX output"),
-				       _("Changes will not be highlighted in LaTeX output "
-					 "when using pdflatex, because xcolor and ulem are not installed.\n"
+					 "because xcolor and ulem are not installed.\n"
 					 "Please install both packages or redefine "
 					 "\\lyxadded and \\lyxdeleted in the LaTeX preamble."));
 		}
@@ -1031,6 +1081,10 @@ bool Buffer::readDocument(Lexer & lex)
 						<< absFileName()
 						<< ") does not include "
 						"this document. Ignoring the master assignment.");
+				// If the master has just been created, un-hide it (#11162)
+				if (!master->fileName().exists())
+					lyx::dispatch(FuncRequest(LFUN_BUFFER_SWITCH,
+								  master->absFileName()));
 			}
 		}
 	}
@@ -1043,16 +1097,18 @@ bool Buffer::readDocument(Lexer & lex)
 		d->old_position = params().origin;
 	else
 		d->old_position = filePath();
+
+	if (!parent())
+		clearIncludeList();
+
 	bool const res = text().read(lex, errorList, d->inset);
 	d->old_position.clear();
 
 	// inform parent buffer about local macros
 	if (parent()) {
 		Buffer const * pbuf = parent();
-		UserMacroSet::const_iterator cit = usermacros.begin();
-		UserMacroSet::const_iterator end = usermacros.end();
-		for (; cit != end; ++cit)
-			pbuf->usermacros.insert(*cit);
+		for (auto const & m : usermacros)
+			pbuf->usermacros.insert(m);
 	}
 	usermacros.clear();
 	updateMacros();
@@ -1061,15 +1117,32 @@ bool Buffer::readDocument(Lexer & lex)
 }
 
 
+bool Buffer::isSyncTeXenabled() const
+{
+	bool enabled = params().output_sync;
+
+	if (!enabled)
+		for (auto const & c : theConverters()) {
+			const string dest = c.to().substr(0,3);
+			if (dest == "dvi" || dest == "pdf") {
+				const string cmd = c.command();
+				enabled |= cmd.find("-synctex=") != string::npos
+					&& cmd.find("-synctex=0") == string::npos;
+				if (enabled)
+					break;
+			}
+		}
+	return enabled;
+}
+
 bool Buffer::importString(string const & format, docstring const & contents, ErrorList & errorList)
 {
-	Format const * fmt = formats.getFormat(format);
+	Format const * fmt = theFormats().getFormat(format);
 	if (!fmt)
 		return false;
 	// It is important to use the correct extension here, since some
 	// converters create a wrong output file otherwise (e.g. html2latex)
-	TempFile const tempfile("Buffer_importStringXXXXXX." + fmt->extension());
-	FileName const name(tempfile.name());
+	FileName const name = tempFileName("Buffer_importStringXXXXXX." + fmt->extension());
 	ofdocstream os(name.toFilesystemEncoding().c_str());
 	// Do not convert os implicitly to bool, since that is forbidden in C++11.
 	bool const success = !(os << contents).fail();
@@ -1085,8 +1158,7 @@ bool Buffer::importString(string const & format, docstring const & contents, Err
 		converted = importFile(format, name, errorList);
 	}
 
-	if (name.exists())
-		name.removeFile();
+	removeTempFile(name);
 	return converted;
 }
 
@@ -1096,10 +1168,14 @@ bool Buffer::importFile(string const & format, FileName const & name, ErrorList
 	if (!theConverters().isReachable(format, "lyx"))
 		return false;
 
-	TempFile const tempfile("Buffer_importFileXXXXXX.lyx");
-	FileName const lyx(tempfile.name());
-	if (theConverters().convert(0, name, lyx, name, format, "lyx", errorList))
-		return readFile(lyx) == ReadSuccess;
+	FileName const lyx = tempFileName("Buffer_importFileXXXXXX.lyx");
+	Converters::RetVal const retval =
+		theConverters().convert(this, name, lyx, name, format, "lyx", errorList);
+	if (retval == Converters::SUCCESS) {
+		bool const success = readFile(lyx) == ReadSuccess;
+		removeTempFile(lyx);
+		return success;
+	}
 
 	return false;
 }
@@ -1136,9 +1212,8 @@ bool Buffer::readString(string const & s)
 
 Buffer::ReadStatus Buffer::readFile(FileName const & fn)
 {
-	FileName fname(fn);
 	Lexer lex;
-	if (!lex.setFile(fname)) {
+	if (!lex.setFile(fn)) {
 		Alert::error(_("File Not Found"),
 			bformat(_("Unable to open file `%1$s'."),
 			        from_utf8(fn.absFileName())));
@@ -1177,7 +1252,7 @@ Buffer::ReadStatus Buffer::readFile(FileName const & fn)
 
 	d->file_fully_loaded = true;
 	d->read_only = !d->filename.isWritable();
-	params().compressed = formats.isZippedFile(d->filename);
+	params().compressed = theFormats().isZippedFile(d->filename);
 	saveCheckSum();
 	return ReadSuccess;
 }
@@ -1195,16 +1270,21 @@ void Buffer::setFullyLoaded(bool value)
 }
 
 
-bool Buffer::lastPreviewError() const
+bool Buffer::freshStartRequired() const
 {
-	return d->preview_error_;
+	return d->require_fresh_start_;
+}
+
+void Buffer::requireFreshStart(bool const b) const
+{
+	d->require_fresh_start_ = b;
 }
 
 
 PreviewLoader * Buffer::loader() const
 {
 	if (!isExporting() && lyxrc.preview == LyXRC::PREVIEW_OFF)
-		return 0;
+		return nullptr;
 	if (!d->preview_loader_)
 		d->preview_loader_ = new PreviewLoader(*this);
 	return d->preview_loader_;
@@ -1214,7 +1294,7 @@ PreviewLoader * Buffer::loader() const
 void Buffer::removePreviews() const
 {
 	delete d->preview_loader_;
-	d->preview_loader_ = 0;
+	d->preview_loader_ = nullptr;
 }
 
 
@@ -1224,9 +1304,9 @@ void Buffer::updatePreviews() const
 	if (!ploader)
 		return;
 
-	InsetIterator it = inset_iterator_begin(*d->inset);
-	InsetIterator const end = inset_iterator_end(*d->inset);
-	for (; it != end; ++it)
+	InsetIterator it = begin(*d->inset);
+	InsetIterator const itend = end(*d->inset);
+	for (; it != itend; ++it)
 		it->addPreview(it, *ploader);
 
 	ploader->startLoading();
@@ -1291,14 +1371,14 @@ Buffer::ReadStatus Buffer::convertLyXFormat(FileName const & fn,
 	command << os::python()
 		<< ' ' << quoteName(lyx2lyx.toFilesystemEncoding())
 		<< " -t " << convert<string>(LYX_FORMAT)
-		<< " -o " << quoteName(tmpfile.toFilesystemEncoding())
+		<< " -o " << quoteName(tmpfile.toSafeFilesystemEncoding())
 		<< ' ' << quoteName(fn.toSafeFilesystemEncoding());
 	string const command_str = command.str();
 
 	LYXERR(Debug::INFO, "Running '" << command_str << '\'');
 
 	cmd_ret const ret = runCommand(command_str);
-	if (ret.first != 0) {
+	if (!ret.valid) {
 		if (from_format < LYX_FORMAT) {
 			Alert::error(_("Conversion script failed"),
 				bformat(_("%1$s is from an older version"
@@ -1320,14 +1400,37 @@ Buffer::ReadStatus Buffer::convertLyXFormat(FileName const & fn,
 
 
 FileName Buffer::getBackupName() const {
+	map<int, string> const file_formats = {
+	  {544, "23"},
+	  {508, "22"},
+	  {474, "21"},
+	  {413, "20"},
+	  {345, "16"},
+	  {276, "15"},
+	  {245, "14"},
+	  {221, "13"},
+	  {220, "12"},
+	  {218, "1163"},
+	  {217, "116"},
+	  {216, "115"},
+	  {215, "11"},
+	  {210, "010"},
+	  {200, "006"}
+	};
 	FileName const & fn = fileName();
 	string const fname = fn.onlyFileNameWithoutExt();
 	string const fext  = fn.extension() + "~";
 	string const fpath = lyxrc.backupdir_path.empty() ?
 		fn.onlyPath().absFileName() :
 		lyxrc.backupdir_path;
-	string const fform = convert<string>(d->file_format);
-	string const backname = fname + "-lyxformat-" + fform;
+	string backup_suffix;
+	// If file format is from a stable series use version instead of file format
+	auto const it = file_formats.find(d->file_format);
+	if (it != file_formats.end())
+		backup_suffix = "-lyx" + it->second;
+	else
+		backup_suffix = "-lyxformat-" + convert<string>(d->file_format);
+	string const backname = fname + backup_suffix;
 	FileName backup(addName(fpath, addExtension(backname, fext)));
 
 	// limit recursion, just in case
@@ -1372,7 +1475,7 @@ bool Buffer::save() const
 	}
 
 	// ask if the disk file has been externally modified (use checksum method)
-	if (fileName().exists() && isExternallyModified(checksum_method)) {
+	if (fileName().exists() && isChecksumModified()) {
 		docstring text =
 			bformat(_("Document %1$s has been externally modified. "
 				"Are you sure you want to overwrite this file?"), file);
@@ -1387,18 +1490,18 @@ bool Buffer::save() const
 
 	// if the file does not yet exist, none of the backup activity
 	// that follows is necessary
-  if (!fileName().exists()) {
+	if (!fileName().exists()) {
 		if (!writeFile(fileName()))
-      return false;
-    markClean();
-    return true;
-  }
+			return false;
+		markClean();
+		return true;
+	}
 
 	// we first write the file to a new name, then move it to its
 	// proper location once that has been done successfully. that
 	// way we preserve the original file if something goes wrong.
 	string const justname = fileName().onlyFileNameWithoutExt();
-	auto tempfile = make_unique<TempFile>(fileName().onlyPath(),
+	auto tempfile = lyx::make_unique<TempFile>(fileName().onlyPath(),
 	                                      justname + "-XXXXXX.lyx");
 	bool const symlink = fileName().isSymLink();
 	if (!symlink)
@@ -1406,6 +1509,9 @@ bool Buffer::save() const
 
 	FileName savefile(tempfile->name());
 	LYXERR(Debug::FILES, "Saving to " << savefile.absFileName());
+	if (!savefile.clonePermissions(fileName()))
+		LYXERR0("Failed to clone the permission from " << fileName().absFileName() << " to " << savefile.absFileName());
+
 	if (!writeFile(savefile))
 		return false;
 
@@ -1464,9 +1570,8 @@ bool Buffer::save() const
 		// time stamp is invalidated by copying/moving
 		saveCheckSum();
 		markClean();
-		if (d->file_format != LYX_FORMAT)
-			// the file associated with this buffer is now in the current format
-			d->file_format = LYX_FORMAT;
+		// the file associated with this buffer is now in the current format
+		d->file_format = LYX_FORMAT;
 		return true;
 	}
 	// else we saved the file, but failed to move it to the right location.
@@ -1533,7 +1638,7 @@ bool Buffer::writeFile(FileName const & fname) const
 }
 
 
-docstring Buffer::emergencyWrite()
+docstring Buffer::emergencyWrite() const
 {
 	// No need to save if the buffer has not changed.
 	if (isClean())
@@ -1583,7 +1688,7 @@ docstring Buffer::emergencyWrite()
 		return user_message;
 	}
 
-	user_message += "  " + _("Save failed! Bummer. Document is lost.");
+	user_message += "  " + _("Save failed! Document is lost.");
 	// Don't try again.
 	markClean();
 	return user_message;
@@ -1603,16 +1708,14 @@ bool Buffer::write(ostream & ofs) const
 	// Important: Keep the version formatting in sync with lyx2lyx and
 	//            tex2lyx (bug 7951)
 	ofs << "#LyX " << lyx_version_major << "." << lyx_version_minor
-	    << " created this file. For more info see http://www.lyx.org/\n"
+	    << " created this file. For more info see https://www.lyx.org/\n"
 	    << "\\lyxformat " << LYX_FORMAT << "\n"
 	    << "\\begin_document\n";
 
 	/// For each author, set 'used' to true if there is a change
 	/// by this author in the document; otherwise set it to 'false'.
-	AuthorList::Authors::const_iterator a_it = params().authors().begin();
-	AuthorList::Authors::const_iterator a_end = params().authors().end();
-	for (; a_it != a_end; ++a_it)
-		a_it->setUsed(false);
+	for (Author const & a : params().authors())
+		a.setUsed(false);
 
 	ParIterator const end = const_cast<Buffer *>(this)->par_iterator_end();
 	ParIterator it = const_cast<Buffer *>(this)->par_iterator_begin();
@@ -1653,38 +1756,33 @@ bool Buffer::write(ostream & ofs) const
 }
 
 
-bool Buffer::makeLaTeXFile(FileName const & fname,
+Buffer::ExportStatus Buffer::makeLaTeXFile(FileName const & fname,
 			   string const & original_path,
 			   OutputParams const & runparams_in,
 			   OutputWhat output) const
 {
 	OutputParams runparams = runparams_in;
 
-	// XeTeX with TeX fonts is only safe with ASCII encoding (see also #9740),
-	// Check here, because the "flavor" is not known in BufferParams::encoding()
-	// (power users can override this safety measure selecting "utf8-plain").
-	if (!params().useNonTeXFonts && (runparams.flavor == OutputParams::XETEX)
-	    && (runparams.encoding->name() != "utf8-plain"))
-		runparams.encoding = encodings.fromLyXName("ascii");
-
 	string const encoding = runparams.encoding->iconvName();
-	LYXERR(Debug::LATEX, "makeLaTeXFile encoding: " << encoding << ", fname=" << fname.realPath());
+	LYXERR(Debug::OUTFILE, "makeLaTeXFile encoding: " << encoding << ", fname=" << fname.realPath());
 
 	ofdocstream ofs;
 	try { ofs.reset(encoding); }
 	catch (iconv_codecvt_facet_exception const & e) {
 		lyxerr << "Caught iconv exception: " << e.what() << endl;
-		Alert::error(_("Iconv software exception Detected"), bformat(_("Please "
-			"verify that the support software for your encoding (%1$s) is "
-			"properly installed"), from_ascii(encoding)));
-		return false;
+		Alert::error(_("Iconv software exception Detected"),
+			bformat(_("Please verify that the `iconv' support software is"
+					  " properly installed and supports the selected encoding"
+					  " (%1$s), or change the encoding in"
+					  " Document>Settings>Language."), from_ascii(encoding)));
+		return ExportError;
 	}
 	if (!openFileWrite(ofs, fname))
-		return false;
+		return ExportError;
 
 	ErrorList & errorList = d->errorLists["Export"];
 	errorList.clear();
-	bool failed_export = false;
+	ExportStatus status = ExportSuccess;
 	otexstream os(ofs);
 
 	// make sure we are ready to export
@@ -1694,42 +1792,56 @@ bool Buffer::makeLaTeXFile(FileName const & fname,
 	updateBuffer();
 	updateMacroInstances(OutputUpdate);
 
+	ExportStatus retval;
 	try {
-		writeLaTeXSource(os, original_path, runparams, output);
+		retval = writeLaTeXSource(os, original_path, runparams, output);
+		if (retval == ExportKilled)
+			return ExportKilled;
 	}
 	catch (EncodingException const & e) {
 		docstring const failed(1, e.failed_char);
 		ostringstream oss;
-		oss << "0x" << hex << e.failed_char << dec;
-		docstring msg = bformat(_("Could not find LaTeX command for character '%1$s'"
-					  " (code point %2$s)"),
-					  failed, from_utf8(oss.str()));
-		errorList.push_back(ErrorItem(msg, _("Some characters of your document are probably not "
-				"representable in the chosen encoding.\n"
-				"Changing the document encoding to utf8 could help."),
-				e.par_id, e.pos, e.pos + 1));
-		failed_export = true;
+		oss << "0x" << hex << static_cast<uint32_t>(e.failed_char) << dec;
+		if (getParFromID(e.par_id).paragraph().layout().pass_thru) {
+			docstring msg = bformat(_("Uncodable character '%1$s'"
+						  " (code point %2$s)"),
+						  failed, from_utf8(oss.str()));
+			errorList.push_back(ErrorItem(msg, _("Some characters of your document are not "
+					"representable in specific verbatim contexts.\n"
+					"Changing the document encoding to utf8 could help."),
+						      {e.par_id, e.pos}, {e.par_id, e.pos + 1}));
+		} else {
+			docstring msg = bformat(_("Could not find LaTeX command for character '%1$s'"
+						  " (code point %2$s)"),
+						  failed, from_utf8(oss.str()));
+			errorList.push_back(ErrorItem(msg, _("Some characters of your document are probably not "
+					"representable in the chosen encoding.\n"
+					"Changing the document encoding to utf8 could help."),
+						      {e.par_id, e.pos}, {e.par_id, e.pos + 1}));
+		}
+		status = ExportError;
 	}
 	catch (iconv_codecvt_facet_exception const & e) {
 		errorList.push_back(ErrorItem(_("iconv conversion failed"),
-			_(e.what()), -1, 0, 0));
-		failed_export = true;
+		                              _(e.what())));
+		status = ExportError;
 	}
 	catch (exception const & e) {
 		errorList.push_back(ErrorItem(_("conversion failed"),
-			_(e.what()), -1, 0, 0));
-		failed_export = true;
+		                              _(e.what())));
+		lyxerr << e.what() << endl;
+		status = ExportError;
 	}
 	catch (...) {
 		lyxerr << "Caught some really weird exception..." << endl;
 		lyx_exit(1);
 	}
 
-	d->texrow = move(os.texrow());
+	d->texrow = std::move(os.texrow());
 
 	ofs.close();
 	if (ofs.fail()) {
-		failed_export = true;
+		status = ExportError;
 		lyxerr << "File '" << fname << "' was not closed properly." << endl;
 	}
 
@@ -1737,11 +1849,11 @@ bool Buffer::makeLaTeXFile(FileName const & fname,
 		errorList.clear();
 	else
 		errors("Export");
-	return !failed_export;
+	return status;
 }
 
 
-void Buffer::writeLaTeXSource(otexstream & os,
+Buffer::ExportStatus Buffer::writeLaTeXSource(otexstream & os,
 			   string const & original_path,
 			   OutputParams const & runparams_in,
 			   OutputWhat output) const
@@ -1750,15 +1862,8 @@ void Buffer::writeLaTeXSource(otexstream & os,
 
 	OutputParams runparams = runparams_in;
 
-	// XeTeX with TeX fonts is only safe with ASCII encoding,
-	// Check here, because the "flavor" is not known in BufferParams::encoding()
-	// (power users can override this safety measure selecting "utf8-plain").
-	if (!params().useNonTeXFonts && (runparams.flavor == OutputParams::XETEX)
-	    && (runparams.encoding->name() != "utf8-plain"))
-		runparams.encoding = encodings.fromLyXName("ascii");
-	// FIXME: when only the current paragraph is shown, this is ignored
-	//        (or not reached) and characters encodable in the current
-	//        encoding are not converted to ASCII-representation.
+	// Some macros rely on font encoding
+	runparams.main_fontenc = params().main_font_encoding();
 
 	// If we are compiling a file standalone, even if this is the
 	// child of some other buffer, let's cut the link here, so the
@@ -1771,13 +1876,16 @@ void Buffer::writeLaTeXSource(otexstream & os,
 	BufferEncodings::initUnicodeMath(*this);
 
 	// validate the buffer.
-	LYXERR(Debug::LATEX, "  Validating buffer...");
+	LYXERR(Debug::OUTFILE, "  Validating buffer...");
 	LaTeXFeatures features(*this, params(), runparams);
 	validate(features);
 	// This is only set once per document (in master)
-	if (!runparams.is_child)
+	if (!runparams.is_child) {
 		runparams.use_polyglossia = features.usePolyglossia();
-	LYXERR(Debug::LATEX, "  Buffer validation done.");
+		runparams.use_hyperref = features.isRequired("hyperref");
+		runparams.use_CJK = features.mustProvide("CJK");
+	}
+	LYXERR(Debug::OUTFILE, "  Buffer validation done.");
 
 	bool const output_preamble =
 		output == FullSource || output == OnlyPreamble;
@@ -1788,7 +1896,7 @@ void Buffer::writeLaTeXSource(otexstream & os,
 	// first paragraph of the document. (Asger)
 	if (output_preamble && runparams.nice) {
 		os << "%% LyX " << lyx_version << " created this file.  "
-			"For more info, see http://www.lyx.org/.\n"
+			"For more info, see https://www.lyx.org/.\n"
 			"%% Do not edit unless you really know what "
 			"you are doing.\n";
 	}
@@ -1817,9 +1925,9 @@ void Buffer::writeLaTeXSource(otexstream & os,
 			docstring uncodable_glyphs;
 			Encoding const * const enc = runparams.encoding;
 			if (enc) {
-				for (size_t n = 0; n < inputpath.size(); ++n) {
-					if (!enc->encodable(inputpath[n])) {
-						docstring const glyph(1, inputpath[n]);
+				for (char_type n : inputpath) {
+					if (!enc->encodable(n)) {
+						docstring const glyph(1, n);
 						LYXERR0("Uncodable character '"
 							<< glyph
 							<< "' in input path!");
@@ -1832,7 +1940,7 @@ void Buffer::writeLaTeXSource(otexstream & os,
 			if (!uncodable_glyphs.empty()) {
 				frontend::Alert::warning(
 					_("Uncodable character in file path"),
-					support::bformat(
+					bformat(
 					  _("The path of your document\n"
 					    "(%1$s)\n"
 					    "contains glyphs that are unknown "
@@ -1850,8 +1958,7 @@ void Buffer::writeLaTeXSource(otexstream & os,
 					    "file path name."),
 					  inputpath, uncodable_glyphs));
 			} else {
-				string docdir =
-					support::latex_path(original_path);
+				string docdir = os::latex_path(original_path);
 				if (contains(docdir, '#')) {
 					docdir = subst(docdir, "#", "\\#");
 					os << "\\catcode`\\#=11"
@@ -1862,9 +1969,27 @@ void Buffer::writeLaTeXSource(otexstream & os,
 					os << "\\catcode`\\%=11"
 					      "\\def\\%{%}\\catcode`\\%=14\n";
 				}
+				if (contains(docdir, '~'))
+					docdir = subst(docdir, "~", "\\string~");
+				bool const nonascii = !isAscii(from_utf8(docdir));
+				// LaTeX 2019/10/01 handles non-ascii path without detokenize
+				bool const utfpathlatex = features.isAvailableAtLeastFrom("LaTeX", 2019, 10);
+				bool const detokenize = !utfpathlatex && nonascii;
+				bool const quote = contains(docdir, ' ');
+				if (utfpathlatex && nonascii)
+					os << "\\UseRawInputEncoding\n";
 				os << "\\makeatletter\n"
-				   << "\\def\\input@path{{"
-				   << docdir << "}}\n"
+				   << "\\def\\input@path{{";
+				if (detokenize)
+					os << "\\detokenize{";
+				if (quote)
+					os << "\"";
+				os << docdir;
+				if (quote)
+					os << "\"";
+				if (detokenize)
+					os << "}";
+				os << "}}\n"
 				   << "\\makeatother\n";
 			}
 		}
@@ -1878,6 +2003,62 @@ void Buffer::writeLaTeXSource(otexstream & os,
 		runparams.use_babel = params().writeLaTeX(os, features,
 							  d->filename.onlyPath());
 
+		// Active characters
+		runparams.active_chars = features.getActiveChars();
+
+		// Biblatex bibliographies are loaded here
+		if (params().useBiblatex()) {
+			vector<pair<docstring, string>> const bibfiles =
+				prepareBibFilePaths(runparams, getBibfiles(), true);
+			for (pair<docstring, string> const & file: bibfiles) {
+				os << "\\addbibresource";
+				if (!file.second.empty())
+					os << "[bibencoding=" << file.second << "]";
+				os << "{" << file.first << "}\n";
+			}
+		}
+
+		if (!runparams.dryrun && features.hasPolyglossiaExclusiveLanguages()
+		    && !features.hasOnlyPolyglossiaLanguages()) {
+			docstring blangs;
+			docstring plangs;
+			vector<string> bll = features.getBabelExclusiveLanguages();
+			vector<string> pll = features.getPolyglossiaExclusiveLanguages();
+			if (!bll.empty()) {
+				docstring langs;
+				for (string const & sit : bll) {
+					if (!langs.empty())
+						langs += ", ";
+					langs += _(sit);
+				}
+				blangs = bll.size() > 1 ?
+					    bformat(_("The languages %1$s are only supported by Babel."), langs)
+					  : bformat(_("The language %1$s is only supported by Babel."), langs);
+			}
+			if (!pll.empty()) {
+				docstring langs;
+				for (string const & pit : pll) {
+					if (!langs.empty())
+						langs += ", ";
+					langs += _(pit);
+				}
+				plangs = pll.size() > 1 ?
+					    bformat(_("The languages %1$s are only supported by Polyglossia."), langs)
+					  : bformat(_("The language %1$s is only supported by Polyglossia."), langs);
+				if (!blangs.empty())
+					plangs += "\n";
+			}
+
+			frontend::Alert::warning(
+				_("Incompatible Languages!"),
+				bformat(
+				  _("You cannot use the following languages "
+				    "together in one LaTeX document because "
+				    "they require conflicting language packages:\n"
+				    "%1$s%2$s"),
+				  plangs, blangs));
+		}
+
 		// Japanese might be required only in some children of a document,
 		// but once required, we must keep use_japanese true.
 		runparams.use_japanese |= features.isRequired("japanese");
@@ -1886,28 +2067,33 @@ void Buffer::writeLaTeXSource(otexstream & os,
 			// Restore the parenthood if needed
 			if (!runparams.is_child)
 				d->ignore_parent = false;
-			return;
+			return ExportSuccess;
 		}
 
 		// make the body.
+		// mark the beginning of the body to separate it from InPreamble insets
+		os.texrow().start(TexRow::beginDocument());
 		os << "\\begin{document}\n";
 
+		// mark the start of a new paragraph by simulating a newline,
+		// so that os.afterParbreak() returns true at document start
+		os.lastChar('\n');
+
 		// output the parent macros
-		MacroSet::iterator it = parentMacros.begin();
-		MacroSet::iterator end = parentMacros.end();
-		for (; it != end; ++it) {
-			int num_lines = (*it)->write(os.os(), true);
+		for (auto const & mac : parentMacros) {
+			int num_lines = mac->write(os.os(), true);
 			os.texrow().newlines(num_lines);
 		}
 
 	} // output_preamble
 
-	os.texrow().start(paragraphs().begin()->id(), 0);
-
 	LYXERR(Debug::INFO, "preamble finished, now the body.");
 
 	// the real stuff
-	latexParagraphs(*this, text(), os, runparams);
+	try {
+		latexParagraphs(*this, text(), os, runparams);
+	}
+	catch (ConversionException const &) { return ExportKilled; }
 
 	// Restore the parenthood if needed
 	if (!runparams.is_child)
@@ -1918,143 +2104,141 @@ void Buffer::writeLaTeXSource(otexstream & os,
 
 	if (output_preamble) {
 		os << "\\end{document}\n";
-		LYXERR(Debug::LATEX, "makeLaTeXFile...done");
+		LYXERR(Debug::OUTFILE, "makeLaTeXFile...done");
 	} else {
-		LYXERR(Debug::LATEX, "LaTeXFile for inclusion made.");
+		LYXERR(Debug::OUTFILE, "LaTeXFile for inclusion made.");
 	}
 	runparams_in.encoding = runparams.encoding;
 
 	LYXERR(Debug::INFO, "Finished making LaTeX file.");
 	LYXERR(Debug::INFO, "Row count was " << os.texrow().rows() - 1 << '.');
+	return ExportSuccess;
 }
 
 
-void Buffer::makeDocBookFile(FileName const & fname,
+Buffer::ExportStatus Buffer::makeDocBookFile(FileName const & fname,
 			      OutputParams const & runparams,
 			      OutputWhat output) const
 {
-	LYXERR(Debug::LATEX, "makeDocBookFile...");
+	LYXERR(Debug::OUTFILE, "makeDocBookFile...");
 
 	ofdocstream ofs;
 	if (!openFileWrite(ofs, fname))
-		return;
+		return ExportError;
 
 	// make sure we are ready to export
 	// this needs to be done before we validate
 	updateBuffer();
 	updateMacroInstances(OutputUpdate);
 
-	writeDocBookSource(ofs, fname.absFileName(), runparams, output);
+	ExportStatus const retval = writeDocBookSource(ofs, runparams, output);
+	if (retval == ExportKilled)
+		return ExportKilled;
 
 	ofs.close();
 	if (ofs.fail())
 		lyxerr << "File '" << fname << "' was not closed properly." << endl;
+	return ExportSuccess;
 }
 
 
-void Buffer::writeDocBookSource(odocstream & os, string const & fname,
+Buffer::ExportStatus Buffer::writeDocBookSource(odocstream & os,
 			     OutputParams const & runparams,
 			     OutputWhat output) const
 {
 	LaTeXFeatures features(*this, params(), runparams);
 	validate(features);
+	d->bibinfo_.makeCitationLabels(*this);
 
 	d->texrow.reset();
 
 	DocumentClass const & tclass = params().documentClass();
-	string const & top_element = tclass.latexname();
 
 	bool const output_preamble =
 		output == FullSource || output == OnlyPreamble;
 	bool const output_body =
-	  output == FullSource || output == OnlyBody;
+		output == FullSource || output == OnlyBody || output == IncludedFile;
 
 	if (output_preamble) {
-		if (runparams.flavor == OutputParams::XML)
-			os << "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n";
-
-		// FIXME UNICODE
-		os << "<!DOCTYPE " << from_ascii(top_element) << ' ';
-
-		// FIXME UNICODE
-		if (! tclass.class_header().empty())
-			os << from_ascii(tclass.class_header());
-		else if (runparams.flavor == OutputParams::XML)
-			os << "PUBLIC \"-//OASIS//DTD DocBook XML//EN\" "
-			    << "\"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd\"";
-		else
-			os << " PUBLIC \"-//OASIS//DTD DocBook V4.2//EN\"";
-
-		docstring preamble = from_utf8(params().preamble);
-		if (runparams.flavor != OutputParams::XML ) {
-			preamble += "<!ENTITY % output.print.png \"IGNORE\">\n";
-			preamble += "<!ENTITY % output.print.pdf \"IGNORE\">\n";
-			preamble += "<!ENTITY % output.print.eps \"IGNORE\">\n";
-			preamble += "<!ENTITY % output.print.bmp \"IGNORE\">\n";
+		// XML preamble, no doctype needed.
+		// Not using XMLStream for this, as the root tag would be in the tag stack and make troubles with the error
+		// detection mechanisms (these are called before the end tag is output, and thus interact with the canary
+		// parsep in output_docbook.cpp).
+		os << "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
+		   << "<!-- This DocBook file was created by LyX " << lyx_version
+		   << "\n  See https://www.lyx.org/ for more information -->\n";
+
+		// Prepare the name space declaration for MathML depending on document preferences.
+		string mathmlNamespace;
+		if (params().docbook_mathml_prefix != BufferParams::NoPrefix) {
+			string mathmlPrefix;
+			if (params().docbook_mathml_prefix == BufferParams::MPrefix)
+				mathmlPrefix = "m";
+			else if (params().docbook_mathml_prefix == BufferParams::MMLPrefix)
+				mathmlPrefix = "mml";
+			mathmlNamespace = + " xmlns:" + mathmlPrefix + "=\"http://www.w3.org/1998/Math/MathML\"";
 		}
 
-		string const name = runparams.nice
-			? changeExtension(absFileName(), ".sgml") : fname;
-		preamble += features.getIncludedFiles(name);
-		preamble += features.getLyXSGMLEntities();
+		// XML-compatible language code: in lib/languages, language codes are
+		// given as dictionary file names; HTML5 expects to follow BCP47. This
+		// function implements a simple heuristic that does the conversion.
+		std::string htmlCode = params().language->code();
+		std::replace(htmlCode.begin(), htmlCode.end(), '_', '-');
 
-		if (!preamble.empty()) {
-			os << "\n [ " << preamble << " ]";
-		}
-		os << ">\n\n";
+		// Directly output the root tag, based on the current type of document.
+		string attributes = "xml:lang=\"" + htmlCode + '"'
+						    + " xmlns=\"http://docbook.org/ns/docbook\""
+						    + " xmlns:xlink=\"http://www.w3.org/1999/xlink\""
+						    + mathmlNamespace
+						    + " xmlns:xi=\"http://www.w3.org/2001/XInclude\""
+						    + " version=\"5.2\"";
+		// Version 5.2 is required for formalgroup.
+
+		os << "<" << from_ascii(tclass.docbookroot()) << " " << from_ascii(attributes) << ">\n";
 	}
 
 	if (output_body) {
-		string top = top_element;
-		top += " lang=\"";
-		if (runparams.flavor == OutputParams::XML)
-			top += params().language->code();
-		else
-			top += params().language->code().substr(0, 2);
-		top += '"';
-
-		if (!params().options.empty()) {
-			top += ' ';
-			top += params().options;
-		}
-
-		os << "<!-- " << ((runparams.flavor == OutputParams::XML)? "XML" : "SGML")
-				<< " file was created by LyX " << lyx_version
-				<< "\n  See http://www.lyx.org/ for more information -->\n";
-
-		params().documentClass().counters().reset();
+		// Start to output the document.
+		XMLStream xs(os);
+		docbookParagraphs(text(), *this, xs, runparams);
+	}
 
-		sgml::openTag(os, top);
-		os << '\n';
-		docbookParagraphs(text(), *this, os, runparams);
-		sgml::closeTag(os, top_element);
+	if (output_preamble) {
+		// Close the root element. No need for a line break, as free text is never allowed
+		// in a root element, it must always be wrapped in some container.
+		os << "</" << from_ascii(tclass.docbookroot()) << ">";
 	}
+
+	return ExportSuccess;
 }
 
 
-void Buffer::makeLyXHTMLFile(FileName const & fname,
+Buffer::ExportStatus Buffer::makeLyXHTMLFile(FileName const & fname,
 			      OutputParams const & runparams) const
 {
-	LYXERR(Debug::LATEX, "makeLyXHTMLFile...");
+	LYXERR(Debug::OUTFILE, "makeLyXHTMLFile...");
 
 	ofdocstream ofs;
 	if (!openFileWrite(ofs, fname))
-		return;
+		return ExportError;
 
 	// make sure we are ready to export
 	// this has to be done before we validate
 	updateBuffer(UpdateMaster, OutputUpdate);
 	updateMacroInstances(OutputUpdate);
 
-	writeLyXHTMLSource(ofs, runparams, FullSource);
+	ExportStatus const retval = writeLyXHTMLSource(ofs, runparams, FullSource);
+	if (retval == ExportKilled)
+		return retval;
 
 	ofs.close();
 	if (ofs.fail())
 		lyxerr << "File '" << fname << "' was not closed properly." << endl;
+	return retval;
 }
 
 
-void Buffer::writeLyXHTMLSource(odocstream & os,
+Buffer::ExportStatus Buffer::writeLyXHTMLSource(odocstream & os,
 			     OutputParams const & runparams,
 			     OutputWhat output) const
 {
@@ -2068,34 +2252,32 @@ void Buffer::writeLyXHTMLSource(odocstream & os,
 	  output == FullSource || output == OnlyBody || output == IncludedFile;
 
 	if (output_preamble) {
-		os << "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
-		   << "<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.1 plus MathML 2.0//EN\" \"http://www.w3.org/Math/DTD/mathml2/xhtml-math11-f.dtd\">\n"
-		   // FIXME Language should be set properly.
-		   << "<html xmlns=\"http://www.w3.org/1999/xhtml\">\n"
+		// HTML5-compatible language code: in lib/languages, language codes are
+		// given as dictionary file names; HTML5 expects to follow BCP47. This
+		// function implements a simple heuristic that does the conversion.
+		std::string htmlCode = params().language->code();
+		std::replace(htmlCode.begin(), htmlCode.end(), '_', '-');
+
+		os << "<!DOCTYPE html>\n"
+		   << "<html xmlns=\"http://www.w3.org/1999/xhtml\" lang=\"" << from_ascii(htmlCode) << "\">\n"
 		   << "<head>\n"
-		   << "<meta name=\"GENERATOR\" content=\"" << PACKAGE_STRING << "\" />\n"
-		   // FIXME Presumably need to set this right
-		   << "<meta http-equiv=\"Content-type\" content=\"text/html;charset=UTF-8\" />\n";
+		   << "<meta name=\"generator\" content=\"" << PACKAGE_STRING << "\" />\n";
 
 		docstring const & doctitle = features.htmlTitle();
 		os << "<title>"
 		   << (doctitle.empty() ?
 		         from_ascii("LyX Document") :
-		         html::htmlize(doctitle, XHTMLStream::ESCAPE_ALL))
+		         xml::escapeString(doctitle, XMLStream::ESCAPE_ALL))
 		   << "</title>\n";
 
 		docstring styles = features.getTClassHTMLPreamble();
 		if (!styles.empty())
 			os << "\n<!-- Text Class Preamble -->\n" << styles << '\n';
 
-		styles = from_utf8(features.getPreambleSnippets());
-		if (!styles.empty())
-			os << "\n<!-- Preamble Snippets -->\n" << styles << '\n';
-
 		// we will collect CSS information in a stream, and then output it
 		// either here, as part of the header, or else in a separate file.
 		odocstringstream css;
-		styles = from_utf8(features.getCSSSnippets());
+		styles = features.getCSSSnippets();
 		if (!styles.empty())
 			css << "/* LyX Provided Styles */\n" << styles << '\n';
 
@@ -2139,7 +2321,7 @@ void Buffer::writeLyXHTMLSource(odocstream & os,
 			// we are here if the CSS is supposed to be written to the header
 			// or if we failed to write it to an external file.
 			if (!written) {
-				os << "<style type='text/css'>\n"
+				os << "<style>\n"
 					 << dstyles
 					 << "\n</style>\n";
 			}
@@ -2151,17 +2333,22 @@ void Buffer::writeLyXHTMLSource(odocstream & os,
 		bool const output_body_tag = (output != IncludedFile);
 		if (output_body_tag)
 			os << "<body dir=\"auto\">\n";
-		XHTMLStream xs(os);
+		XMLStream xs(os);
 		if (output != IncludedFile)
 			// if we're an included file, the counters are in the master.
 			params().documentClass().counters().reset();
-		xhtmlParagraphs(text(), *this, xs, runparams);
+		try {
+			xhtmlParagraphs(text(), *this, xs, runparams);
+		}
+		catch (ConversionException const &) { return ExportKilled; }
 		if (output_body_tag)
 			os << "</body>\n";
 	}
 
 	if (output_preamble)
 		os << "</html>\n";
+
+	return ExportSuccess;
 }
 
 
@@ -2181,10 +2368,15 @@ int Buffer::runChktex()
 
 	// Generate the LaTeX file if neccessary
 	OutputParams runparams(&params().encoding());
-	runparams.flavor = OutputParams::LATEX;
+	runparams.flavor = Flavor::LaTeX;
 	runparams.nice = false;
 	runparams.linelen = lyxrc.plaintext_linelen;
-	makeLaTeXFile(FileName(name), org_path, runparams);
+	ExportStatus const retval =
+		makeLaTeXFile(FileName(name), org_path, runparams);
+	if (retval != ExportSuccess) {
+		// error code on failure
+		return -1;
+	}
 
 	TeXErrors terr;
 	Chktex chktex(lyxrc.chktex_command, onlyFileName(name), filePath());
@@ -2218,16 +2410,19 @@ void Buffer::validate(LaTeXFeatures & features) const
 	if (!features.runparams().is_child)
 		params().validate(features);
 
+	if (!parent())
+		clearIncludeList();
+
 	for (Paragraph const & p : paragraphs())
 		p.validate(features);
 
-	if (lyxerr.debugging(Debug::LATEX)) {
+	if (lyxerr.debugging(Debug::OUTFILE)) {
 		features.showStruct();
 	}
 }
 
 
-void Buffer::getLabelList(vector<docstring> & list) const
+void Buffer::getLabelList(vector<std::tuple<docstring, docstring, docstring>> & list) const
 {
 	// If this is a child document, use the master's list instead.
 	if (parent()) {
@@ -2237,49 +2432,11 @@ void Buffer::getLabelList(vector<docstring> & list) const
 
 	list.clear();
 	shared_ptr<Toc> toc = d->toc_backend.toc("label");
-	Toc::const_iterator toc_it = toc->begin();
-	Toc::const_iterator end = toc->end();
-	for (; toc_it != end; ++toc_it) {
-		if (toc_it->depth() == 0)
-			list.push_back(toc_it->str());
-	}
-}
-
-
-void Buffer::updateBibfilesCache(UpdateScope scope) const
-{
-	// FIXME This is probably unnecssary, given where we call this.
-	// If this is a child document, use the parent's cache instead.
-	if (parent() && scope != UpdateChildOnly) {
-		masterBuffer()->updateBibfilesCache();
-		return;
-	}
-
-	d->bibfiles_cache_.clear();
-	for (InsetIterator it = inset_iterator_begin(inset()); it; ++it) {
-		if (it->lyxCode() == BIBTEX_CODE) {
-			InsetBibtex const & inset = static_cast<InsetBibtex const &>(*it);
-			support::FileNameList const bibfiles = inset.getBibFiles();
-			d->bibfiles_cache_.insert(d->bibfiles_cache_.end(),
-				bibfiles.begin(),
-				bibfiles.end());
-		} else if (it->lyxCode() == INCLUDE_CODE) {
-			InsetInclude & inset = static_cast<InsetInclude &>(*it);
-			Buffer const * const incbuf = inset.getChildBuffer();
-			if (!incbuf)
-				continue;
-			support::FileNameList const & bibfiles =
-					incbuf->getBibfilesCache(UpdateChildOnly);
-			if (!bibfiles.empty()) {
-				d->bibfiles_cache_.insert(d->bibfiles_cache_.end(),
-					bibfiles.begin(),
-					bibfiles.end());
-			}
+	for (auto const & tocit : *toc) {
+		if (tocit.depth() == 0) {
+			list.push_back(make_tuple(tocit.str(), tocit.asString(), tocit.prettyStr()));
 		}
 	}
-	d->bibfile_cache_valid_ = true;
-	d->bibinfo_cache_valid_ = false;
-	d->cite_labels_valid_ = false;
 }
 
 
@@ -2287,6 +2444,7 @@ void Buffer::invalidateBibinfoCache() const
 {
 	d->bibinfo_cache_valid_ = false;
 	d->cite_labels_valid_ = false;
+	scheduleBiblioTempRemoval();
 	// also invalidate the cache for the parent buffer
 	Buffer const * const pbuf = d->parent();
 	if (pbuf)
@@ -2294,28 +2452,19 @@ void Buffer::invalidateBibinfoCache() const
 }
 
 
-void Buffer::invalidateBibfileCache() const
-{
-	d->bibfile_cache_valid_ = false;
-	d->bibinfo_cache_valid_ = false;
-	d->cite_labels_valid_ = false;
-	// also invalidate the cache for the parent buffer
-	Buffer const * const pbuf = d->parent();
-	if (pbuf)
-		pbuf->invalidateBibfileCache();
-}
-
-
-support::FileNameList const & Buffer::getBibfilesCache(UpdateScope scope) const
+docstring_list const & Buffer::getBibfiles(UpdateScope scope) const
 {
 	// FIXME This is probably unnecessary, given where we call this.
-	// If this is a child document, use the master's cache instead.
+	// If this is a child document, use the master instead.
 	Buffer const * const pbuf = masterBuffer();
 	if (pbuf != this && scope != UpdateChildOnly)
-		return pbuf->getBibfilesCache();
+		return pbuf->getBibfiles();
 
-	if (!d->bibfile_cache_valid_)
-		this->updateBibfilesCache(scope);
+	// In 2.3.x, we have:
+	//if (!d->bibfile_cache_valid_)
+	//	this->updateBibfilesCache(scope);
+	// I think that is a leftover, but there have been so many back-
+	// and-forths with this, due to Windows issues, that I am not sure.
 
 	return d->bibfiles_cache_;
 }
@@ -2330,6 +2479,63 @@ BiblioInfo const & Buffer::masterBibInfo() const
 }
 
 
+BiblioInfo const & Buffer::bibInfo() const
+{
+	return d->bibinfo_;
+}
+
+
+void Buffer::registerBibfiles(const docstring_list & bf) const
+{
+	// We register the bib files in the master buffer,
+	// if there is one, but also in every single buffer,
+	// in case a child is compiled alone.
+	Buffer const * const tmp = masterBuffer();
+	if (tmp != this)
+		tmp->registerBibfiles(bf);
+
+	for (auto const & p : bf) {
+		docstring_list::const_iterator temp =
+			find(d->bibfiles_cache_.begin(), d->bibfiles_cache_.end(), p);
+		if (temp == d->bibfiles_cache_.end())
+			d->bibfiles_cache_.push_back(p);
+	}
+}
+
+
+static map<docstring, FileName> bibfileCache;
+
+FileName Buffer::getBibfilePath(docstring const & bibid) const
+{
+	map<docstring, FileName>::const_iterator it =
+		bibfileCache.find(bibid);
+	if (it != bibfileCache.end()) {
+		// i.e., return bibfileCache[bibid];
+		return it->second;
+	}
+
+	LYXERR(Debug::FILES, "Reading file location for " << bibid);
+	string const texfile = changeExtension(to_utf8(bibid), "bib");
+	// we need to check first if this file exists where it's said to be.
+	// there's a weird bug that occurs otherwise: if the file is in the
+	// Buffer's directory but has the same name as some file that would be
+	// found by kpsewhich, then we find the latter, not the former.
+	FileName const local_file = makeAbsPath(texfile, filePath());
+	FileName file = local_file;
+	if (!file.exists()) {
+		// there's no need now to check whether the file can be found
+		// locally
+		file = findtexfile(texfile, "bib", true);
+		if (file.empty())
+			file = local_file;
+	}
+	LYXERR(Debug::FILES, "Found at: " << file);
+
+	bibfileCache[bibid] = file;
+	return bibfileCache[bibid];
+}
+
+
 void Buffer::checkIfBibInfoCacheIsValid() const
 {
 	// use the master's cache
@@ -2339,63 +2545,127 @@ void Buffer::checkIfBibInfoCacheIsValid() const
 		return;
 	}
 
+	// If we already know the cache is invalid, stop here.
+	// This is important in the case when the bibliography
+	// environment (rather than Bib[la]TeX) is used.
+	// In that case, the timestamp check below gives no
+	// sensible result. Rather than that, the cache will
+	// be invalidated explicitly via invalidateBibInfoCache()
+	// by the Bibitem inset.
+	// Same applies for bib encoding changes, which trigger
+	// invalidateBibInfoCache() by InsetBibtex.
+	if (!d->bibinfo_cache_valid_)
+		return;
+
+	if (d->have_bibitems_) {
+		// We have a bibliography environment.
+		// Invalidate the bibinfo cache unconditionally.
+		// Cite labels will get invalidated by the inset if needed.
+		d->bibinfo_cache_valid_ = false;
+		return;
+	}
+
+	// OK. This is with Bib(la)tex. We'll assume the cache
+	// is valid and change this if we find changes in the bibs.
+	d->bibinfo_cache_valid_ = true;
+	d->cite_labels_valid_ = true;
+
 	// compare the cached timestamps with the actual ones.
-	FileNameList const & bibfiles_cache = getBibfilesCache();
-	FileNameList::const_iterator ei = bibfiles_cache.begin();
-	FileNameList::const_iterator en = bibfiles_cache.end();
-	for (; ei != en; ++ ei) {
-		time_t lastw = ei->lastModified();
-		time_t prevw = d->bibfile_status_[*ei];
+	docstring_list const & bibfiles_cache = getBibfiles();
+	for (auto const & bf : bibfiles_cache) {
+		FileName const fn = getBibfilePath(bf);
+		time_t lastw = fn.lastModified();
+		time_t prevw = d->bibfile_status_[fn];
 		if (lastw != prevw) {
 			d->bibinfo_cache_valid_ = false;
 			d->cite_labels_valid_ = false;
-			d->bibfile_status_[*ei] = lastw;
+			d->bibfile_status_[fn] = lastw;
 		}
 	}
 }
 
 
-void Buffer::reloadBibInfoCache() const
+void Buffer::clearBibFileCache() const
 {
+	bibfileCache.clear();
+}
+
+
+void Buffer::reloadBibInfoCache(bool const force) const
+{
+	// we should not need to do this for internal buffers
+	if (isInternal())
+		return;
+
 	// use the master's cache
 	Buffer const * const tmp = masterBuffer();
 	if (tmp != this) {
-		tmp->reloadBibInfoCache();
+		tmp->reloadBibInfoCache(force);
 		return;
 	}
 
-	checkIfBibInfoCacheIsValid();
-	if (d->bibinfo_cache_valid_)
-		return;
+	if (!force) {
+		checkIfBibInfoCacheIsValid();
+		if (d->bibinfo_cache_valid_)
+			return;
+	}
 
+	LYXERR(Debug::FILES, "Bibinfo cache was invalid.");
+	// re-read file locations when this info changes
+	// FIXME Is this sufficient? Or should we also force that
+	// in some other cases? If so, then it is easy enough to
+	// add the following line in some other places.
+	clearBibFileCache();
 	d->bibinfo_.clear();
-	collectBibKeys();
+	FileNameList checkedFiles;
+	d->have_bibitems_ = false;
+	collectBibKeys(checkedFiles);
 	d->bibinfo_cache_valid_ = true;
 }
 
 
-void Buffer::collectBibKeys() const
+void Buffer::collectBibKeys(FileNameList & checkedFiles) const
 {
-	for (InsetIterator it = inset_iterator_begin(inset()); it; ++it)
-		it->collectBibKeys(it);
+	if (!parent())
+		clearIncludeList();
+
+	for (InsetIterator it = begin(inset()); it; ++it) {
+		it->collectBibKeys(it, checkedFiles);
+		if (it->lyxCode() == BIBITEM_CODE) {
+			if (parent() != nullptr)
+				parent()->d->have_bibitems_ = true;
+			else
+				d->have_bibitems_ = true;
+		}
+	}
 }
 
 
-void Buffer::addBiblioInfo(BiblioInfo const & bi) const
+void Buffer::addBiblioInfo(BiblioInfo const & bi_in) const
 {
-	Buffer const * tmp = masterBuffer();
-	BiblioInfo & masterbi = (tmp == this) ?
-		d->bibinfo_ : tmp->d->bibinfo_;
-	masterbi.mergeBiblioInfo(bi);
+	// We add the biblio info to the parent buffer,
+	// if there is one, but also to this buffer, in case
+	// it is compiled alone.
+	BiblioInfo & our_bi = d->bibinfo_;
+	our_bi.mergeBiblioInfo(bi_in);
+
+	if (parent())
+		parent()->addBiblioInfo(bi_in);
 }
 
 
-void Buffer::addBibTeXInfo(docstring const & key, BibTeXInfo const & bi) const
+void Buffer::addBibTeXInfo(docstring const & key, BibTeXInfo const & bin) const
 {
-	Buffer const * tmp = masterBuffer();
-	BiblioInfo & masterbi = (tmp == this) ?
-		d->bibinfo_ : tmp->d->bibinfo_;
-	masterbi[key] = bi;
+	// We add the bibtex info to the master buffer,
+	// if there is one, but also to every single buffer,
+	// in case a child is compiled alone.
+	BiblioInfo & bi = d->bibinfo_;
+	bi[key] = bin;
+
+	if (parent() != nullptr) {
+		BiblioInfo & masterbi = masterBuffer()->d->bibinfo_;
+		masterbi[key] = bin;
+	}
 }
 
 
@@ -2406,6 +2676,11 @@ void Buffer::makeCitationLabels() const
 }
 
 
+void Buffer::invalidateCiteLabels() const
+{
+	masterBuffer()->d->cite_labels_valid_ = false;
+}
+
 bool Buffer::citeLabelsValid() const
 {
 	return masterBuffer()->d->cite_labels_valid_;
@@ -2427,6 +2702,7 @@ void Buffer::removeBiblioTempFiles() const
 	Buffer const * const pbuf = parent();
 	if (pbuf)
 		pbuf->removeBiblioTempFiles();
+	removeBiblioTemps = false;
 }
 
 
@@ -2445,7 +2721,25 @@ void Buffer::markDepClean(string const & name)
 }
 
 
-bool Buffer::getStatus(FuncRequest const & cmd, FuncStatus & flag)
+bool Buffer::branchActivationEnabled(FuncCode act, docstring const & branch) const
+{
+	bool const master = act == LFUN_BRANCH_MASTER_ACTIVATE
+	                    || act == LFUN_BRANCH_MASTER_DEACTIVATE;
+	bool const activate = act == LFUN_BRANCH_ACTIVATE
+	                    || act == LFUN_BRANCH_MASTER_ACTIVATE;
+	Buffer const * buf = master ? masterBuffer() : this;
+	Branch const * our_branch = buf->params().branchlist().find(branch);
+	// Can be disabled if
+	// - this is  a _MASTER_ command and there is no master
+	// - the relevant buffer does not know the branch
+	// - the branch is already in the desired state
+	return ((!master || parent() != nullptr)
+	        && !branch.empty() && our_branch
+	        && our_branch->isSelected() != activate);
+}
+
+
+bool Buffer::getStatus(FuncRequest const & cmd, FuncStatus & flag) const
 {
 	if (isInternal()) {
 		// FIXME? if there is an Buffer LFUN that can be dispatched even
@@ -2458,7 +2752,7 @@ bool Buffer::getStatus(FuncRequest const & cmd, FuncStatus & flag)
 	switch (cmd.action()) {
 
 	case LFUN_BUFFER_TOGGLE_READ_ONLY:
-		flag.setOnOff(isReadonly());
+		flag.setOnOff(hasReadonlyFlag());
 		break;
 
 		// FIXME: There is need for a command-line import.
@@ -2472,42 +2766,36 @@ bool Buffer::getStatus(FuncRequest const & cmd, FuncStatus & flag)
 		break;
 
 	case LFUN_BUFFER_EXPORT: {
-		docstring const arg = cmd.argument();
+		docstring const & arg = cmd.argument();
 		if (arg == "custom") {
 			enable = true;
 			break;
 		}
-		string format = to_utf8(arg);
+		string format = (arg.empty() || arg == "default") ?
+			params().getDefaultOutputFormat() : to_utf8(arg);
 		size_t pos = format.find(' ');
 		if (pos != string::npos)
 			format = format.substr(0, pos);
-		enable = params().isExportable(format);
+		enable = params().isExportable(format, false);
 		if (!enable)
 			flag.message(bformat(
 					     _("Don't know how to export to format: %1$s"), arg));
 		break;
-	}
-
-	case LFUN_BUFFER_CHKTEX:
-		enable = params().isLatex() && !lyxrc.chktex_command.empty();
-		break;
+	}
 
 	case LFUN_BUILD_PROGRAM:
-		enable = params().isExportable("program");
+		enable = params().isExportable("program", false);
 		break;
 
 	case LFUN_BRANCH_ACTIVATE:
 	case LFUN_BRANCH_DEACTIVATE:
 	case LFUN_BRANCH_MASTER_ACTIVATE:
-	case LFUN_BRANCH_MASTER_DEACTIVATE: {
-		bool const master = (cmd.action() == LFUN_BRANCH_MASTER_ACTIVATE
-				     || cmd.action() == LFUN_BRANCH_MASTER_DEACTIVATE);
-		BranchList const & branchList = master ? masterBuffer()->params().branchlist()
-			: params().branchlist();
-		docstring const branchName = cmd.argument();
-		flag.setEnabled(!branchName.empty() && branchList.find(branchName));
+	case LFUN_BRANCH_MASTER_DEACTIVATE:
+		// Let a branch inset handle that
+		if (cmd.argument().empty())
+			return false;
+		flag.setEnabled(branchActivationEnabled(cmd.action(), cmd.argument()));
 		break;
-	}
 
 	case LFUN_BRANCH_ADD:
 	case LFUN_BRANCHES_RENAME:
@@ -2533,15 +2821,16 @@ bool Buffer::getStatus(FuncRequest const & cmd, FuncStatus & flag)
 		flag.setOnOff(params().output_changes);
 		break;
 
-	case LFUN_BUFFER_TOGGLE_COMPRESSION: {
+	case LFUN_BUFFER_TOGGLE_COMPRESSION:
 		flag.setOnOff(params().compressed);
 		break;
-	}
 
-	case LFUN_BUFFER_TOGGLE_OUTPUT_SYNC: {
+	case LFUN_BUFFER_TOGGLE_OUTPUT_SYNC:
 		flag.setOnOff(params().output_sync);
 		break;
-	}
+
+	case LFUN_BUFFER_ANONYMIZE:
+		break;
 
 	default:
 		return false;
@@ -2551,6 +2840,53 @@ bool Buffer::getStatus(FuncRequest const & cmd, FuncStatus & flag)
 }
 
 
+bool Buffer::branchActivationDispatch(FuncCode act, docstring const & branch)
+{
+	bool const master = (act == LFUN_BRANCH_MASTER_ACTIVATE
+			     || act == LFUN_BRANCH_MASTER_DEACTIVATE);
+	bool const activate = (act == LFUN_BRANCH_ACTIVATE
+			       || act == LFUN_BRANCH_MASTER_ACTIVATE);
+	Buffer * buf = master ? const_cast<Buffer *>(masterBuffer()) : this;
+	Branch * our_branch = buf->params().branchlist().find(branch);
+
+	// See comment in branchActivationStatus
+	if ((master && parent() == nullptr)
+	     || !our_branch
+	     || our_branch->isSelected() == activate)
+		return false;
+
+	if (master && !buf->hasGuiDelegate()
+	    && (!theApp() || !theApp()->unhide(buf)))
+		// at least issue a warning for now (ugly, but better than dataloss).
+		frontend::Alert::warning(_("Branch state changes in master document"),
+		    lyx::support::bformat(_("The state of the branch '%1$s' "
+			"was changed in the master file. "
+			"Please make sure to save the master."), branch), true);
+
+	UndoGroupHelper ugh(buf);
+	buf->undo().recordUndoBufferParams(CursorData());
+	our_branch->setSelected(activate);
+	// cur.forceBufferUpdate() is not enough)
+	buf->updateBuffer();
+
+	// if branch exists in a descendant, update previews.
+	// TODO: only needed if "Show preview" is enabled in the included inset.
+	bool exists_in_desc = false;
+	for (auto const & it : buf->getDescendants()) {
+		if (it->params().branchlist().find(branch))
+			exists_in_desc = true;
+	}
+	if (exists_in_desc) {
+		// TODO: ideally we would only update the previews of the
+		// specific children that have this branch directly or
+		// in one of their descendants
+		buf->removePreviews();
+		buf->updatePreviews();
+	}
+	return true;
+}
+
+
 void Buffer::dispatch(string const & command, DispatchResult & result)
 {
 	return dispatch(lyxaction.lookupFunc(command), result);
@@ -2562,6 +2898,7 @@ void Buffer::dispatch(string const & command, DispatchResult & result)
 // whether we have a GUI or not. The boolean use_gui holds this information.
 void Buffer::dispatch(FuncRequest const & func, DispatchResult & dr)
 {
+	LYXERR(Debug::ACTION, "Buffer::dispatch: cmd: " << func);
 	if (isInternal()) {
 		// FIXME? if there is an Buffer LFUN that can be dispatched even
 		// if internal, put a switch '(cmd.action())' here.
@@ -2571,7 +2908,8 @@ void Buffer::dispatch(FuncRequest const & func, DispatchResult & dr)
 	string const argument = to_utf8(func.argument());
 	// We'll set this back to false if need be.
 	bool dispatched = true;
-	undo().beginUndoGroup();
+	// This handles undo groups automagically
+	UndoGroupHelper ugh(this);
 
 	switch (func.action()) {
 	case LFUN_BUFFER_TOGGLE_READ_ONLY:
@@ -2581,15 +2919,17 @@ void Buffer::dispatch(FuncRequest const & func, DispatchResult & dr)
 				dr.setMessage(log);
 		}
 		else
-			setReadonly(!isReadonly());
+			setReadonly(!hasReadonlyFlag());
 		break;
 
 	case LFUN_BUFFER_EXPORT: {
-		ExportStatus const status = doExport(argument, false);
+		string const format = (argument.empty() || argument == "default") ?
+			params().getDefaultOutputFormat() : argument;
+		ExportStatus const status = doExport(format, false);
 		dr.setError(status != ExportSuccess);
 		if (status != ExportSuccess)
 			dr.setMessage(bformat(_("Error exporting to format: %1$s."),
-					      func.argument()));
+			                      from_utf8(format)));
 		break;
 	}
 
@@ -2601,14 +2941,10 @@ void Buffer::dispatch(FuncRequest const & func, DispatchResult & dr)
 		break;
 	}
 
-	case LFUN_BUFFER_CHKTEX:
-		runChktex();
-		break;
-
 	case LFUN_BUFFER_EXPORT_CUSTOM: {
 		string format_name;
 		string command = split(argument, format_name, ' ');
-		Format const * format = formats.getFormat(format_name);
+		Format const * format = theFormats().getFormat(format_name);
 		if (!format) {
 			lyxerr << "Format \"" << format_name
 				<< "\" not recognized!"
@@ -2661,51 +2997,29 @@ void Buffer::dispatch(FuncRequest const & func, DispatchResult & dr)
 	case LFUN_BRANCH_DEACTIVATE:
 	case LFUN_BRANCH_MASTER_ACTIVATE:
 	case LFUN_BRANCH_MASTER_DEACTIVATE: {
-		bool const master = (func.action() == LFUN_BRANCH_MASTER_ACTIVATE
-				     || func.action() == LFUN_BRANCH_MASTER_DEACTIVATE);
-		Buffer * buf = master ? const_cast<Buffer *>(masterBuffer())
-				      : this;
-
-		docstring const branch_name = func.argument();
-		// the case without a branch name is handled elsewhere
-		if (branch_name.empty()) {
-			dispatched = false;
-			break;
-		}
-		Branch * branch = buf->params().branchlist().find(branch_name);
-		if (!branch) {
-			LYXERR0("Branch " << branch_name << " does not exist.");
-			dr.setError(true);
-			docstring const msg =
-				bformat(_("Branch \"%1$s\" does not exist."), branch_name);
-			dr.setMessage(msg);
-			break;
+		// Let a branch inset handle that
+		if (func.argument().empty()) {
+			dr.dispatched(false);
+			return;
 		}
-		bool const activate = (func.action() == LFUN_BRANCH_ACTIVATE
-				       || func.action() == LFUN_BRANCH_MASTER_ACTIVATE);
-		if (branch->isSelected() != activate) {
-			buf->undo().recordUndoBufferParams(CursorData());
-			branch->setSelected(activate);
-			dr.setError(false);
+		bool const res = branchActivationDispatch(func.action(), func.argument());
+		dr.setError(!res);
+		if (res)
 			dr.screenUpdate(Update::Force);
-			dr.forceBufferUpdate();
-		}
 		break;
 	}
 
 	case LFUN_BRANCH_ADD: {
-		docstring branch_name = func.argument();
-		if (branch_name.empty()) {
+		docstring const & branchnames = func.argument();
+		if (branchnames.empty()) {
 			dispatched = false;
 			break;
 		}
 		BranchList & branch_list = params().branchlist();
 		vector<docstring> const branches =
-			getVectorFromString(branch_name, branch_list.separator());
+			getVectorFromString(branchnames, branch_list.separator());
 		docstring msg;
-		for (vector<docstring>::const_iterator it = branches.begin();
-		     it != branches.end(); ++it) {
-			branch_name = *it;
+		for (docstring const & branch_name : branches) {
 			Branch * branch = branch_list.find(branch_name);
 			if (branch) {
 				LYXERR0("Branch " << branch_name << " already exists.");
@@ -2717,9 +3031,9 @@ void Buffer::dispatch(FuncRequest const & func, DispatchResult & dr)
 				undo().recordUndoBufferParams(CursorData());
 				branch_list.add(branch_name);
 				branch = branch_list.find(branch_name);
-				string const x11hexname = X11hexname(branch->color());
-				docstring const str = branch_name + ' ' + from_ascii(x11hexname);
-				lyx::dispatch(FuncRequest(LFUN_SET_COLOR, str));
+				if (branch)
+					// needed to update the color table for dark mode
+					branch->setColors("background", "background");
 				dr.setError(false);
 				dr.screenUpdate(Update::Force);
 			}
@@ -2735,10 +3049,10 @@ void Buffer::dispatch(FuncRequest const & func, DispatchResult & dr)
 
 		docstring const oldname = from_utf8(func.getArg(0));
 		docstring const newname = from_utf8(func.getArg(1));
-		InsetIterator it  = inset_iterator_begin(inset());
-		InsetIterator const end = inset_iterator_end(inset());
+		InsetIterator it  = begin(inset());
+		InsetIterator const itend = end(inset());
 		bool success = false;
-		for (; it != end; ++it) {
+		for (; it != itend; ++it) {
 			if (it->lyxCode() == BRANCH_CODE) {
 				InsetBranch & ins = static_cast<InsetBranch &>(*it);
 				if (ins.branch() == oldname) {
@@ -2752,7 +3066,7 @@ void Buffer::dispatch(FuncRequest const & func, DispatchResult & dr)
 				// get buffer of external file
 				InsetInclude const & ins =
 					static_cast<InsetInclude const &>(*it);
-				Buffer * child = ins.getChildBuffer();
+				Buffer * child = ins.loadIfNeeded();
 				if (!child)
 					continue;
 				child->dispatch(func, dr);
@@ -2767,7 +3081,7 @@ void Buffer::dispatch(FuncRequest const & func, DispatchResult & dr)
 	}
 
 	case LFUN_BUFFER_VIEW_CACHE:
-		if (!formats.view(*this, d->preview_file_,
+		if (!theFormats().view(*this, d->preview_file_,
 				  d->preview_format_))
 			dr.setMessage(_("Error viewing the output file."));
 		break;
@@ -2776,8 +3090,6 @@ void Buffer::dispatch(FuncRequest const & func, DispatchResult & dr)
 		if (params().save_transient_properties)
 			undo().recordUndoBufferParams(CursorData());
 		params().track_changes = !params().track_changes;
-		if (!params().track_changes)
-			dr.forceChangesUpdate();
 		break;
 
 	case LFUN_CHANGES_OUTPUT:
@@ -2785,20 +3097,13 @@ void Buffer::dispatch(FuncRequest const & func, DispatchResult & dr)
 			undo().recordUndoBufferParams(CursorData());
 		params().output_changes = !params().output_changes;
 		if (params().output_changes) {
-			bool dvipost    = LaTeXFeatures::isAvailable("dvipost");
 			bool xcolorulem = LaTeXFeatures::isAvailable("ulem") &&
 					  LaTeXFeatures::isAvailable("xcolor");
 
-			if (!dvipost && !xcolorulem) {
+			if (!xcolorulem) {
 				Alert::warning(_("Changes not shown in LaTeX output"),
 					       _("Changes will not be highlighted in LaTeX output, "
-						 "because neither dvipost nor xcolor/ulem are installed.\n"
-						 "Please install these packages or redefine "
-						 "\\lyxadded and \\lyxdeleted in the LaTeX preamble."));
-			} else if (!xcolorulem) {
-				Alert::warning(_("Changes not shown in LaTeX output"),
-					       _("Changes will not be highlighted in LaTeX output "
-						 "when using pdflatex, because xcolor and ulem are not installed.\n"
+						 "because xcolor and ulem are not installed.\n"
 						 "Please install both packages or redefine "
 						 "\\lyxadded and \\lyxdeleted in the LaTeX preamble."));
 			}
@@ -2816,12 +3121,21 @@ void Buffer::dispatch(FuncRequest const & func, DispatchResult & dr)
 		params().output_sync = !params().output_sync;
 		break;
 
+	case LFUN_BUFFER_ANONYMIZE: {
+		undo().recordUndoFullBuffer(CursorData());
+		CursorData cur(doc_iterator_begin(this));
+		for ( ; cur ; cur.forwardPar())
+			cur.paragraph().anonymize();
+		dr.forceBufferUpdate();
+		dr.screenUpdate(Update::Force);
+		break;
+	}
+
 	default:
 		dispatched = false;
 		break;
 	}
 	dr.dispatched(dispatched);
-	undo().endUndoGroup();
 }
 
 
@@ -2830,9 +3144,10 @@ void Buffer::changeLanguage(Language const * from, Language const * to)
 	LASSERT(from, return);
 	LASSERT(to, return);
 
-	for_each(par_iterator_begin(),
-		 par_iterator_end(),
-		 bind(&Paragraph::changeLanguage, _1, params(), from, to));
+	ParIterator it = par_iterator_begin();
+	ParIterator eit = par_iterator_end();
+	for (; it != eit; ++it)
+		it->changeLanguage(params(), from, to);
 }
 
 
@@ -2849,37 +3164,33 @@ bool Buffer::isMultiLingual() const
 
 std::set<Language const *> Buffer::getLanguages() const
 {
-	std::set<Language const *> languages;
-	getLanguages(languages);
-	return languages;
+	std::set<Language const *> langs;
+	getLanguages(langs);
+	return langs;
 }
 
 
-void Buffer::getLanguages(std::set<Language const *> & languages) const
+void Buffer::getLanguages(std::set<Language const *> & langs) const
 {
 	ParConstIterator end = par_iterator_end();
 	// add the buffer language, even if it's not actively used
-	languages.insert(language());
+	langs.insert(language());
 	// iterate over the paragraphs
 	for (ParConstIterator it = par_iterator_begin(); it != end; ++it)
-		it->getLanguages(languages);
+		it->getLanguages(langs);
 	// also children
-	ListOfBuffers clist = getDescendents();
-	ListOfBuffers::const_iterator cit = clist.begin();
-	ListOfBuffers::const_iterator const cen = clist.end();
-	for (; cit != cen; ++cit)
-		(*cit)->getLanguages(languages);
+	ListOfBuffers clist = getDescendants();
+	for (auto const & cit : clist)
+		cit->getLanguages(langs);
 }
 
 
 DocIterator Buffer::getParFromID(int const id) const
 {
 	Buffer * buf = const_cast<Buffer *>(this);
-	if (id < 0) {
-		// John says this is called with id == -1 from undo
-		lyxerr << "getParFromID(), id: " << id << endl;
+	if (id < 0)
+		// This means non-existent
 		return doc_iterator_end(buf);
-	}
 
 	for (DocIterator it = doc_iterator_begin(buf); !it.atEnd(); it.forwardPar())
 		if (it.paragraph().id() == id)
@@ -2918,6 +3229,11 @@ ParConstIterator Buffer::par_iterator_end() const
 	return ParConstIterator(doc_iterator_end(this));
 }
 
+bool Buffer::empty() const
+{
+	return paragraphs().size() == 1 && paragraphs().front().empty();
+}
+
 
 Language const * Buffer::language() const
 {
@@ -2925,7 +3241,7 @@ Language const * Buffer::language() const
 }
 
 
-docstring const Buffer::B_(string const & l10n) const
+docstring Buffer::B_(string const & l10n) const
 {
 	return params().B_(l10n);
 }
@@ -2937,29 +3253,19 @@ bool Buffer::isClean() const
 }
 
 
-bool Buffer::isExternallyModified(CheckMethod method) const
+bool Buffer::isChecksumModified() const
 {
 	LASSERT(d->filename.exists(), return false);
-	// if method == timestamp, check timestamp before checksum
-	return (method == checksum_method
-		|| d->timestamp_ != d->filename.lastModified())
-		&& d->checksum_ != d->filename.checksum();
+	return d->checksum_ != d->filename.checksum();
 }
 
 
 void Buffer::saveCheckSum() const
 {
 	FileName const & file = d->filename;
-
 	file.refresh();
-	if (file.exists()) {
-		d->timestamp_ = file.lastModified();
-		d->checksum_ = file.checksum();
-	} else {
-		// in the case of save to a new file.
-		d->timestamp_ = 0;
-		d->checksum_ = 0;
-	}
+	d->checksum_ = file.exists() ? file.checksum()
+		: 0; // in the case of save to a new file.
 }
 
 
@@ -2973,6 +3279,7 @@ void Buffer::markClean() const
 	// autosave
 	d->bak_clean = true;
 	d->undo_.markDirty();
+	clearExternalModification();
 }
 
 
@@ -3013,11 +3320,8 @@ void Buffer::markDirty()
 	}
 	d->bak_clean = false;
 
-	DepClean::iterator it = d->dep_clean.begin();
-	DepClean::const_iterator const end = d->dep_clean.end();
-
-	for (; it != end; ++it)
-		it->second = false;
+	for (auto & depit : d->dep_clean)
+		depit.second = false;
 }
 
 
@@ -3062,6 +3366,142 @@ DocFileName Buffer::getReferencedFileName(string const & fn) const
 }
 
 
+string const Buffer::prepareFileNameForLaTeX(string const & name,
+					     string const & ext, bool nice) const
+{
+	string const fname = makeAbsPath(name, filePath()).absFileName();
+	if (FileName::isAbsolute(name) || !FileName(fname + ext).isReadableFile())
+		return name;
+	if (!nice)
+		return fname;
+
+	// FIXME UNICODE
+	return to_utf8(makeRelPath(from_utf8(fname),
+		from_utf8(masterBuffer()->filePath())));
+}
+
+
+vector<pair<docstring, string>> const Buffer::prepareBibFilePaths(OutputParams const & runparams,
+						docstring_list const & bibfilelist,
+						bool const add_extension) const
+{
+	// If we are processing the LaTeX file in a temp directory then
+	// copy the .bib databases to this temp directory, mangling their
+	// names in the process. Store this mangled name in the list of
+	// all databases.
+	// (We need to do all this because BibTeX *really*, *really*
+	// can't handle "files with spaces" and Windows users tend to
+	// use such filenames.)
+	// Otherwise, store the (maybe absolute) path to the original,
+	// unmangled database name.
+
+	vector<pair<docstring, string>> res;
+
+	// determine the export format
+	string const tex_format = flavor2format(runparams.flavor);
+
+	// check for spaces in paths
+	bool found_space = false;
+
+	for (auto const & bit : bibfilelist) {
+		string utf8input = to_utf8(bit);
+		string database =
+			prepareFileNameForLaTeX(utf8input, ".bib", runparams.nice);
+		FileName try_in_file =
+			makeAbsPath(database + ".bib", filePath());
+		bool not_from_texmf = try_in_file.isReadableFile();
+		// If the file has not been found, try with the real file name
+		// (it might come from a child in a sub-directory)
+		if (!not_from_texmf) {
+			try_in_file = getBibfilePath(bit);
+			if (try_in_file.isReadableFile()) {
+				// Check if the file is in texmf
+				FileName kpsefile(findtexfile(changeExtension(utf8input, "bib"), "bib", true));
+				not_from_texmf = kpsefile.empty()
+						|| kpsefile.absFileName() != try_in_file.absFileName();
+				if (not_from_texmf)
+					// If this exists, make path relative to the master
+					// FIXME Unicode
+					database =
+						removeExtension(prepareFileNameForLaTeX(
+											to_utf8(makeRelPath(from_utf8(try_in_file.absFileName()),
+																from_utf8(filePath()))),
+											".bib", runparams.nice));
+			}
+		}
+
+		if (!runparams.inComment && !runparams.dryrun && !runparams.nice &&
+		    not_from_texmf) {
+			// mangledFileName() needs the extension
+			DocFileName const in_file = DocFileName(try_in_file);
+			database = removeExtension(in_file.mangledFileName());
+			FileName const out_file = makeAbsPath(database + ".bib",
+					masterBuffer()->temppath());
+			bool const success = in_file.copyTo(out_file);
+			if (!success) {
+				LYXERR0("Failed to copy '" << in_file
+				       << "' to '" << out_file << "'");
+			}
+		} else if (!runparams.inComment && runparams.nice && not_from_texmf) {
+			runparams.exportdata->addExternalFile(tex_format, try_in_file, database + ".bib");
+			if (!isValidLaTeXFileName(database)) {
+				frontend::Alert::warning(_("Invalid filename"),
+					 _("The following filename will cause troubles "
+					       "when running the exported file through LaTeX: ") +
+					     from_utf8(database));
+			}
+			if (!isValidDVIFileName(database)) {
+				frontend::Alert::warning(_("Problematic filename for DVI"),
+					 _("The following filename can cause troubles "
+					       "when running the exported file through LaTeX "
+						   "and opening the resulting DVI: ") +
+					     from_utf8(database), true);
+			}
+		}
+
+		if (add_extension)
+			database += ".bib";
+
+		// FIXME UNICODE
+		docstring const path = from_utf8(latex_path(database));
+
+		if (contains(path, ' '))
+			found_space = true;
+		string enc;
+		if (params().useBiblatex() && !params().bibFileEncoding(utf8input).empty())
+			enc = params().bibFileEncoding(utf8input);
+
+		bool recorded = false;
+		for (auto const & pe : res) {
+			if (pe.first == path) {
+				recorded = true;
+				break;
+			}
+
+		}
+		if (!recorded)
+			res.push_back(make_pair(path, enc));
+	}
+
+	// Check if there are spaces in the path and warn BibTeX users, if so.
+	// (biber can cope with such paths)
+	if (!prefixIs(runparams.bibtex_command, "biber")) {
+		// Post this warning only once.
+		static bool warned_about_spaces = false;
+		if (!warned_about_spaces &&
+		    runparams.nice && found_space) {
+			warned_about_spaces = true;
+			Alert::warning(_("Export Warning!"),
+				       _("There are spaces in the paths to your BibTeX databases.\n"
+						      "BibTeX will be unable to find them."));
+		}
+	}
+
+	return res;
+}
+
+
+
 string Buffer::layoutPos() const
 {
 	return d->layout_position;
@@ -3085,16 +3525,51 @@ void Buffer::setLayoutPos(string const & path)
 }
 
 
-bool Buffer::isReadonly() const
+bool Buffer::hasReadonlyFlag() const
 {
 	return d->read_only;
 }
 
 
+bool Buffer::isReadonly() const
+{
+	return hasReadonlyFlag() || notifiesExternalModification();
+}
+
+
 void Buffer::setParent(Buffer const * buffer)
 {
-	// Avoids recursive include.
-	d->setParent(buffer == this ? 0 : buffer);
+	// We need to do some work here to avoid recursive parent structures.
+	// This is the easy case.
+	if (buffer == this) {
+		LYXERR0("Ignoring attempt to set self as parent in\n" << fileName());
+		return;
+	}
+	// Now we check parents going upward, to make sure that IF we set the
+	// parent as requested, we would not generate a recursive include.
+	set<Buffer const *> sb;
+	Buffer const * b = buffer;
+	bool found_recursion = false;
+	while (b) {
+		if (sb.find(b) != sb.end()) {
+			found_recursion = true;
+			break;
+		}
+		sb.insert(b);
+		b = b->parent();
+	}
+
+	if (found_recursion) {
+		LYXERR0("Ignoring attempt to set parent of\n" <<
+			fileName() <<
+			"\nto " <<
+			buffer->fileName() <<
+			"\nbecause that would create a recursive inclusion.");
+		return;
+	}
+
+	// We should be safe now.
+	d->setParent(buffer);
 	updateMacros();
 }
 
@@ -3107,7 +3582,7 @@ Buffer const * Buffer::parent() const
 
 ListOfBuffers Buffer::allRelatives() const
 {
-	ListOfBuffers lb = masterBuffer()->getDescendents();
+	ListOfBuffers lb = masterBuffer()->getDescendants();
 	lb.push_front(const_cast<Buffer *>(masterBuffer()));
 	return lb;
 }
@@ -3115,8 +3590,6 @@ ListOfBuffers Buffer::allRelatives() const
 
 Buffer const * Buffer::masterBuffer() const
 {
-	// FIXME Should be make sure we are not in some kind
-	// of recursive include? A -> B -> A will crash this.
 	Buffer const * const pbuf = d->parent();
 	if (!pbuf)
 		return this;
@@ -3147,21 +3620,19 @@ bool Buffer::hasChildren() const
 }
 
 
-void Buffer::collectChildren(ListOfBuffers & clist, bool grand_children) const
+void Buffer::collectChildren(ListOfBuffers & children, bool grand_children) const
 {
 	// loop over children
-	Impl::BufferPositionMap::iterator it = d->children_positions.begin();
-	Impl::BufferPositionMap::iterator end = d->children_positions.end();
-	for (; it != end; ++it) {
-		Buffer * child = const_cast<Buffer *>(it->first);
+	for (auto const & p : d->children_positions) {
+		Buffer * child = const_cast<Buffer *>(p.first);
 		// No duplicates
-		ListOfBuffers::const_iterator bit = find(clist.begin(), clist.end(), child);
-		if (bit != clist.end())
+		ListOfBuffers::const_iterator bit = find(children.begin(), children.end(), child);
+		if (bit != children.end())
 			continue;
-		clist.push_back(child);
+		children.push_back(child);
 		if (grand_children)
 			// there might be grandchildren
-			child->collectChildren(clist, true);
+			child->collectChildren(children, true);
 	}
 }
 
@@ -3180,7 +3651,7 @@ ListOfBuffers Buffer::getChildren() const
 }
 
 
-ListOfBuffers Buffer::getDescendents() const
+ListOfBuffers Buffer::getDescendants() const
 {
 	ListOfBuffers v;
 	collectChildren(v, true);
@@ -3204,7 +3675,7 @@ typename M::const_iterator greatest_below(M & m, typename M::key_type const & x)
 	if (it == m.begin())
 		return m.end();
 
-	it--;
+	--it;
 	return it;
 }
 
@@ -3216,11 +3687,11 @@ MacroData const * Buffer::Impl::getBufferMacro(docstring const & name,
 
 	// if paragraphs have no macro context set, pos will be empty
 	if (pos.empty())
-		return 0;
+		return nullptr;
 
 	// we haven't found anything yet
 	DocIterator bestPos = owner_->par_iterator_begin();
-	MacroData const * bestData = 0;
+	MacroData const * bestData = nullptr;
 
 	// find macro definitions for name
 	NamePositionScopeMacroMap::const_iterator nameIt = macros.find(name);
@@ -3291,11 +3762,11 @@ MacroData const * Buffer::getMacro(docstring const & name,
 	DocIterator const & pos, bool global) const
 {
 	if (d->macro_lock)
-		return 0;
+		return nullptr;
 
 	// query buffer macros
 	MacroData const * data = d->getBufferMacro(name, pos);
-	if (data != 0)
+	if (data != nullptr)
 		return data;
 
 	// If there is a master buffer, query that
@@ -3311,11 +3782,11 @@ MacroData const * Buffer::getMacro(docstring const & name,
 
 	if (global) {
 		data = MacroTable::globalMacros().get(name);
-		if (data != 0)
+		if (data != nullptr)
 			return data;
 	}
 
-	return 0;
+	return nullptr;
 }
 
 
@@ -3335,7 +3806,7 @@ MacroData const * Buffer::getMacro(docstring const & name,
 	// look where the child buffer is included first
 	Impl::BufferPositionMap::iterator it = d->children_positions.find(&child);
 	if (it == d->children_positions.end())
-		return 0;
+		return nullptr;
 
 	// check for macros at the inclusion position
 	return getMacro(name, it->second, global);
@@ -3351,16 +3822,13 @@ void Buffer::Impl::updateMacros(DocIterator & it, DocIterator & scope)
 		Paragraph & par = it.paragraph();
 
 		// iterate over the insets of the current paragraph
-		InsetList const & insets = par.insetList();
-		InsetList::const_iterator iit = insets.begin();
-		InsetList::const_iterator end = insets.end();
-		for (; iit != end; ++iit) {
-			it.pos() = iit->pos;
+		for (auto const & insit : par.insetList()) {
+			it.pos() = insit.pos;
 
 			// is it a nested text inset?
-			if (iit->inset->asInsetText()) {
+			if (insit.inset->asInsetText()) {
 				// Inset needs its own scope?
-				InsetText const * itext = iit->inset->asInsetText();
+				InsetText const * itext = insit.inset->asInsetText();
 				bool newScope = itext->isMacroScope();
 
 				// scope which ends just behind the inset
@@ -3368,14 +3836,14 @@ void Buffer::Impl::updateMacros(DocIterator & it, DocIterator & scope)
 				++insetScope.pos();
 
 				// collect macros in inset
-				it.push_back(CursorSlice(*iit->inset));
+				it.push_back(CursorSlice(*insit.inset));
 				updateMacros(it, newScope ? insetScope : scope);
 				it.pop_back();
 				continue;
 			}
 
-			if (iit->inset->asInsetTabular()) {
-				CursorSlice slice(*iit->inset);
+			if (insit.inset->asInsetTabular()) {
+				CursorSlice slice(*insit.inset);
 				size_t const numcells = slice.nargs();
 				for (; slice.idx() < numcells; slice.forwardIdx()) {
 					it.push_back(slice);
@@ -3386,40 +3854,38 @@ void Buffer::Impl::updateMacros(DocIterator & it, DocIterator & scope)
 			}
 
 			// is it an external file?
-			if (iit->inset->lyxCode() == INCLUDE_CODE) {
+			if (insit.inset->lyxCode() == INCLUDE_CODE) {
 				// get buffer of external file
-				InsetInclude const & inset =
-					static_cast<InsetInclude const &>(*iit->inset);
+				InsetInclude const & incinset =
+					static_cast<InsetInclude const &>(*insit.inset);
 				macro_lock = true;
-				Buffer * child = inset.getChildBuffer();
+				Buffer * child = incinset.loadIfNeeded();
 				macro_lock = false;
 				if (!child)
 					continue;
 
 				// register its position, but only when it is
 				// included first in the buffer
-				if (children_positions.find(child) ==
-					children_positions.end())
-						children_positions[child] = it;
+				children_positions.insert({child, it});
 
 				// register child with its scope
 				position_to_children[it] = Impl::ScopeBuffer(scope, child);
 				continue;
 			}
 
-			InsetMath * im = iit->inset->asInsetMath();
+			InsetMath * im = insit.inset->asInsetMath();
 			if (doing_export && im)  {
 				InsetMathHull * hull = im->asHullInset();
 				if (hull)
 					hull->recordLocation(it);
 			}
 
-			if (iit->inset->lyxCode() != MATHMACRO_CODE)
+			if (insit.inset->lyxCode() != MATHMACRO_CODE)
 				continue;
 
 			// get macro data
-			MathMacroTemplate & macroTemplate =
-				*iit->inset->asInsetMath()->asMacroTemplate();
+			InsetMathMacroTemplate & macroTemplate =
+				*insit.inset->asInsetMath()->asMacroTemplate();
 			MacroContext mc(owner_, it);
 			macroTemplate.updateToContext(mc);
 
@@ -3435,7 +3901,7 @@ void Buffer::Impl::updateMacros(DocIterator & it, DocIterator & scope)
 			// FIXME (Abdel), I don't understand why we pass 'it' here
 			// instead of 'macroTemplate' defined above... is this correct?
 			macros[macroTemplate.name()][it] =
-				Impl::ScopeMacro(scope, MacroData(const_cast<Buffer *>(owner_), it));
+				Impl::ScopeMacro(scope, MacroData(owner_, it));
 		}
 
 		// next paragraph
@@ -3470,11 +3936,9 @@ void Buffer::updateMacros() const
 
 void Buffer::getUsedBranches(std::list<docstring> & result, bool const from_master) const
 {
-	InsetIterator it  = inset_iterator_begin(inset());
-	InsetIterator const end = inset_iterator_end(inset());
-	for (; it != end; ++it) {
-		if (it->lyxCode() == BRANCH_CODE) {
-			InsetBranch & br = static_cast<InsetBranch &>(*it);
+	for (Inset const & it : inset()) {
+		if (it.lyxCode() == BRANCH_CODE) {
+			InsetBranch const & br = static_cast<InsetBranch const &>(it);
 			docstring const name = br.branch();
 			if (!from_master && !params().branchlist().find(name))
 				result.push_back(name);
@@ -3482,11 +3946,11 @@ void Buffer::getUsedBranches(std::list<docstring> & result, bool const from_mast
 				result.push_back(name);
 			continue;
 		}
-		if (it->lyxCode() == INCLUDE_CODE) {
+		if (it.lyxCode() == INCLUDE_CODE) {
 			// get buffer of external file
 			InsetInclude const & ins =
-				static_cast<InsetInclude const &>(*it);
-			Buffer * child = ins.getChildBuffer();
+				static_cast<InsetInclude const &>(it);
+			Buffer * child = ins.loadIfNeeded();
 			if (!child)
 				continue;
 			child->getUsedBranches(result, true);
@@ -3511,11 +3975,11 @@ void Buffer::updateMacroInstances(UpdateType utype) const
 			continue;
 
 		// update macro in all cells of the InsetMathNest
-		DocIterator::idx_type n = minset->nargs();
+		idx_type n = minset->nargs();
 		MacroContext mc = MacroContext(this, it);
-		for (DocIterator::idx_type i = 0; i < n; ++i) {
+		for (idx_type i = 0; i < n; ++i) {
 			MathData & data = minset->cell(i);
-			data.updateMacros(0, mc, utype);
+			data.updateMacros(nullptr, mc, utype, 0);
 		}
 	}
 }
@@ -3529,16 +3993,16 @@ void Buffer::listMacroNames(MacroNameSet & macros) const
 	d->macro_lock = true;
 
 	// loop over macro names
-	Impl::NamePositionScopeMacroMap::iterator nameIt = d->macros.begin();
-	Impl::NamePositionScopeMacroMap::iterator nameEnd = d->macros.end();
-	for (; nameIt != nameEnd; ++nameIt)
-		macros.insert(nameIt->first);
+	for (auto const & nameit : d->macros)
+		macros.insert(nameit.first);
 
 	// loop over children
-	Impl::BufferPositionMap::iterator it = d->children_positions.begin();
-	Impl::BufferPositionMap::iterator end = d->children_positions.end();
-	for (; it != end; ++it)
-		it->first->listMacroNames(macros);
+	for (auto const & p : d->children_positions) {
+		Buffer * child = const_cast<Buffer *>(p.first);
+		// The buffer might have been closed (see #10766).
+		if (theBufferList().isLoaded(child))
+			child->listMacroNames(macros);
+	}
 
 	// call parent
 	Buffer const * const pbuf = d->parent();
@@ -3559,16 +4023,13 @@ void Buffer::listParentMacros(MacroSet & macros, LaTeXFeatures & features) const
 	pbuf->listMacroNames(names);
 
 	// resolve macros
-	MacroNameSet::iterator it = names.begin();
-	MacroNameSet::iterator end = names.end();
-	for (; it != end; ++it) {
+	for (auto const & mit : names) {
 		// defined?
-		MacroData const * data =
-		pbuf->getMacro(*it, *this, false);
+		MacroData const * data = pbuf->getMacro(mit, *this, false);
 		if (data) {
 			macros.insert(data);
 
-			// we cannot access the original MathMacroTemplate anymore
+			// we cannot access the original InsetMathMacroTemplate anymore
 			// here to calls validate method. So we do its work here manually.
 			// FIXME: somehow make the template accessible here.
 			if (data->optionals() > 0)
@@ -3585,13 +4046,12 @@ Buffer::References & Buffer::getReferenceCache(docstring const & label)
 
 	RefCache::iterator it = d->ref_cache_.find(label);
 	if (it != d->ref_cache_.end())
-		return it->second.second;
+		return it->second;
 
-	static InsetLabel const * dummy_il = 0;
 	static References const dummy_refs = References();
 	it = d->ref_cache_.insert(
-		make_pair(label, make_pair(dummy_il, dummy_refs))).first;
-	return it->second.second;
+		make_pair(label, dummy_refs)).first;
+	return it->second;
 }
 
 
@@ -3608,22 +4068,40 @@ void Buffer::addReference(docstring const & label, Inset * inset, ParIterator it
 }
 
 
-void Buffer::setInsetLabel(docstring const & label, InsetLabel const * il)
+void Buffer::setInsetLabel(docstring const & label, InsetLabel const * il,
+			   bool const active)
+{
+	LabelInfo linfo;
+	linfo.label = label;
+	linfo.inset = il;
+	linfo.active = active;
+	masterBuffer()->d->label_cache_.push_back(linfo);
+}
+
+
+InsetLabel const * Buffer::insetLabel(docstring const & label,
+				      bool const active) const
 {
-	masterBuffer()->d->ref_cache_[label].first = il;
+	for (auto const & rc : masterBuffer()->d->label_cache_) {
+		if (rc.label == label && (rc.active || !active))
+			return rc.inset;
+	}
+	return nullptr;
 }
 
 
-InsetLabel const * Buffer::insetLabel(docstring const & label) const
+bool Buffer::activeLabel(docstring const & label) const
 {
-	return masterBuffer()->d->ref_cache_[label].first;
+	return insetLabel(label, true) != nullptr;
 }
 
 
 void Buffer::clearReferenceCache() const
 {
-	if (!d->parent())
+	if (!d->parent()) {
 		d->ref_cache_.clear();
+		d->label_cache_.clear();
+	}
 }
 
 
@@ -3633,26 +4111,25 @@ void Buffer::changeRefsIfUnique(docstring const & from, docstring const & to)
 	reloadBibInfoCache();
 
 	// Check if the label 'from' appears more than once
-	BiblioInfo const & keys = masterBibInfo();
-	BiblioInfo::const_iterator bit  = keys.begin();
-	BiblioInfo::const_iterator bend = keys.end();
 	vector<docstring> labels;
-
-	for (; bit != bend; ++bit)
-		// FIXME UNICODE
-		labels.push_back(bit->first);
+	for (auto const & bibit : masterBibInfo())
+		labels.push_back(bibit.first);
 
 	if (count(labels.begin(), labels.end(), from) > 1)
 		return;
 
 	string const paramName = "key";
-	for (InsetIterator it = inset_iterator_begin(inset()); it; ++it) {
+	UndoGroupHelper ugh(this);
+	InsetIterator it = begin(inset());
+	for (; it; ++it) {
 		if (it->lyxCode() != CITE_CODE)
 			continue;
 		InsetCommand * inset = it->asInsetCommand();
 		docstring const oldValue = inset->getParam(paramName);
-		if (oldValue == from)
+		if (oldValue == from) {
+			undo().recordUndo(CursorData(it));
 			inset->setParam(paramName, to);
+		}
 	}
 }
 
@@ -3669,39 +4146,54 @@ unique_ptr<TexRow> Buffer::getSourceCode(odocstream & os, string const & format,
 	// No side effect of file copying and image conversion
 	runparams.dryrun = true;
 
+	// Some macros rely on font encoding
+	runparams.main_fontenc = params().main_font_encoding();
+
+	// Use the right wrapping for the comment at the beginning of the generated
+	// snippet, so that it is either valid LaTeX or valid XML (including HTML and DocBook).
+	docstring comment_start = from_ascii("% ");
+	docstring comment_end = from_ascii("");
+	if (runparams.flavor == Flavor::Html || runparams.flavor == Flavor::DocBook5) {
+		comment_start = from_ascii("<!-- ");
+		comment_end = from_ascii(" -->");
+	}
+
 	if (output == CurrentParagraph) {
 		runparams.par_begin = par_begin;
 		runparams.par_end = par_end;
 		if (par_begin + 1 == par_end) {
-			os << "% "
+			os << comment_start
 			   << bformat(_("Preview source code for paragraph %1$d"), par_begin)
+			   << comment_end
 			   << "\n\n";
 		} else {
-			os << "% "
+			os << comment_start
 			   << bformat(_("Preview source code from paragraph %1$s to %2$s"),
 					convert<docstring>(par_begin),
 					convert<docstring>(par_end - 1))
+			   << comment_end
 			   << "\n\n";
 		}
 		// output paragraphs
-		if (runparams.flavor == OutputParams::LYX) {
+		if (runparams.flavor == Flavor::LyX) {
 			Paragraph const & par = text().paragraphs()[par_begin];
 			ostringstream ods;
 			depth_type dt = par.getDepth();
 			par.write(ods, params(), dt);
 			os << from_utf8(ods.str());
-		} else if (runparams.flavor == OutputParams::HTML) {
-			XHTMLStream xs(os);
+		} else if (runparams.flavor == Flavor::Html) {
+			XMLStream xs(os);
 			setMathFlavor(runparams);
 			xhtmlParagraphs(text(), *this, xs, runparams);
-		} else if (runparams.flavor == OutputParams::TEXT) {
+		} else if (runparams.flavor == Flavor::Text) {
 			bool dummy = false;
 			// FIXME Handles only one paragraph, unlike the others.
 			// Probably should have some routine with a signature like them.
 			writePlaintextParagraph(*this,
 				text().paragraphs()[par_begin], os, runparams, dummy);
-		} else if (params().isDocBook()) {
-			docbookParagraphs(text(), *this, os, runparams);
+		} else if (runparams.flavor == Flavor::DocBook5) {
+			XMLStream xs{os};
+			docbookParagraphs(text(), *this, xs, runparams);
 		} else {
 			// If we are previewing a paragraph, even if this is the
 			// child of some other buffer, let's cut the link here,
@@ -3713,8 +4205,10 @@ unique_ptr<TexRow> Buffer::getSourceCode(odocstream & os, string const & format,
 			// in order to know if we should output polyglossia
 			// macros (instead of babel macros)
 			LaTeXFeatures features(*this, params(), runparams);
-			params().validate(features);
+			validate(features);
 			runparams.use_polyglossia = features.usePolyglossia();
+			runparams.use_babel = features.useBabel();
+			runparams.use_hyperref = features.isRequired("hyperref");
 			// latex or literate
 			otexstream ots(os);
 			// output above
@@ -3728,15 +4222,16 @@ unique_ptr<TexRow> Buffer::getSourceCode(odocstream & os, string const & format,
 				d->ignore_parent = false;
 		}
 	} else {
-		os << "% ";
+		os << comment_start;
 		if (output == FullSource)
 			os << _("Preview source code");
 		else if (output == OnlyPreamble)
 			os << _("Preview preamble");
 		else if (output == OnlyBody)
 			os << _("Preview body");
+		os << comment_end;
 		os << "\n\n";
-		if (runparams.flavor == OutputParams::LYX) {
+		if (runparams.flavor == Flavor::LyX) {
 			ostringstream ods;
 			if (output == FullSource)
 				write(ods);
@@ -3745,15 +4240,15 @@ unique_ptr<TexRow> Buffer::getSourceCode(odocstream & os, string const & format,
 			else if (output == OnlyBody)
 				text().write(ods);
 			os << from_utf8(ods.str());
-		} else if (runparams.flavor == OutputParams::HTML) {
+		} else if (runparams.flavor == Flavor::Html) {
 			writeLyXHTMLSource(os, runparams, output);
-		} else if (runparams.flavor == OutputParams::TEXT) {
-			if (output == OnlyPreamble) {
+		} else if (runparams.flavor == Flavor::Text) {
+			if (output == OnlyPreamble)
 				os << "% "<< _("Plain text does not have a preamble.");
-			} else
+			else
 				writePlaintextFile(*this, os, runparams);
-		} else if (params().isDocBook()) {
-				writeDocBookSource(os, absFileName(), runparams, output);
+		} else if (runparams.flavor == Flavor::DocBook5) {
+			writeDocBookSource(os, runparams, output);
 		} else {
 			// latex or literate
 			otexstream ots(os);
@@ -3761,6 +4256,7 @@ unique_ptr<TexRow> Buffer::getSourceCode(odocstream & os, string const & format,
 			ots.texrow().newlines(2);
 			if (master)
 				runparams.is_child = true;
+			updateBuffer();
 			writeLaTeXSource(ots, string(), runparams, output);
 			texrow = ots.releaseTexRow();
 		}
@@ -3818,6 +4314,13 @@ void Buffer::updateTitles() const
 }
 
 
+void Buffer::scheduleRedrawWorkAreas() const
+{
+	if (d->wa_)
+		d->wa_->scheduleRedraw();
+}
+
+
 void Buffer::resetAutosaveTimers() const
 {
 	if (d->gui_)
@@ -3837,91 +4340,6 @@ void Buffer::setGuiDelegate(frontend::GuiBufferDelegate * gui)
 }
 
 
-
-namespace {
-
-class AutoSaveBuffer : public ForkedProcess {
-public:
-	///
-	AutoSaveBuffer(Buffer const & buffer, FileName const & fname)
-		: buffer_(buffer), fname_(fname) {}
-	///
-	virtual shared_ptr<ForkedProcess> clone() const
-	{
-		return make_shared<AutoSaveBuffer>(*this);
-	}
-	///
-	int start()
-	{
-		command_ = to_utf8(bformat(_("Auto-saving %1$s"),
-						 from_utf8(fname_.absFileName())));
-		return run(DontWait);
-	}
-private:
-	///
-	virtual int generateChild();
-	///
-	Buffer const & buffer_;
-	FileName fname_;
-};
-
-
-int AutoSaveBuffer::generateChild()
-{
-#if defined(__APPLE__)
-	/* FIXME fork() is not usable for autosave on Mac OS X 10.6 (snow leopard)
-	 *   We should use something else like threads.
-	 *
-	 * Since I do not know how to determine at run time what is the OS X
-	 * version, I just disable forking altogether for now (JMarc)
-	 */
-	pid_t const pid = -1;
-#else
-	// tmp_ret will be located (usually) in /tmp
-	// will that be a problem?
-	// Note that this calls ForkedCalls::fork(), so it's
-	// ok cross-platform.
-	pid_t const pid = fork();
-	// If you want to debug the autosave
-	// you should set pid to -1, and comment out the fork.
-	if (pid != 0 && pid != -1)
-		return pid;
-#endif
-
-	// pid = -1 signifies that lyx was unable
-	// to fork. But we will do the save
-	// anyway.
-	bool failed = false;
-	TempFile tempfile("lyxautoXXXXXX.lyx");
-	tempfile.setAutoRemove(false);
-	FileName const tmp_ret = tempfile.name();
-	if (!tmp_ret.empty()) {
-		if (!buffer_.writeFile(tmp_ret))
-			failed = true;
-		else if (!tmp_ret.moveTo(fname_))
-			failed = true;
-	} else
-		failed = true;
-
-	if (failed) {
-		// failed to write/rename tmp_ret so try writing direct
-		if (!buffer_.writeFile(fname_)) {
-			// It is dangerous to do this in the child,
-			// but safe in the parent, so...
-			if (pid == -1) // emit message signal.
-				buffer_.message(_("Autosave failed!"));
-		}
-	}
-
-	if (pid == 0) // we are the child so...
-		_exit(0);
-
-	return pid;
-}
-
-} // namespace anon
-
-
 FileName Buffer::getEmergencyFileName() const
 {
 	return FileName(d->filename.absFileName() + ".emergency");
@@ -3954,7 +4372,7 @@ void Buffer::removeAutosaveFile() const
 }
 
 
-void Buffer::moveAutosaveFile(support::FileName const & oldauto) const
+void Buffer::moveAutosaveFile(FileName const & oldauto) const
 {
 	FileName const newauto = getAutosaveFileName();
 	oldauto.refresh();
@@ -3967,7 +4385,7 @@ void Buffer::moveAutosaveFile(support::FileName const & oldauto) const
 bool Buffer::autoSave() const
 {
 	Buffer const * buf = d->cloned_buffer_ ? d->cloned_buffer_ : this;
-	if (buf->d->bak_clean || isReadonly())
+	if (buf->d->bak_clean || hasReadonlyFlag())
 		return true;
 
 	message(_("Autosaving current document..."));
@@ -3995,11 +4413,9 @@ bool Buffer::autoSave() const
 void Buffer::setExportStatus(bool e) const
 {
 	d->doing_export = e;
-	ListOfBuffers clist = getDescendents();
-	ListOfBuffers::const_iterator cit = clist.begin();
-	ListOfBuffers::const_iterator const cen = clist.end();
-	for (; cit != cen; ++cit)
-		(*cit)->d->doing_export = e;
+	ListOfBuffers clist = getDescendants();
+	for (auto const & bit : clist)
+		bit->d->doing_export = e;
 }
 
 
@@ -4020,7 +4436,7 @@ Buffer::ExportStatus Buffer::doExport(string const & target, bool put_in_tempdir
 	string & result_file) const
 {
 	bool const update_unincluded =
-			params().maintain_unincluded_children
+			params().maintain_unincluded_children != BufferParams::CM_None
 			&& !params().getIncludedChildren().empty();
 
 	// (1) export with all included children (omit \includeonly)
@@ -4037,6 +4453,9 @@ Buffer::ExportStatus Buffer::doExport(string const & target, bool put_in_tempdir
 
 void Buffer::setMathFlavor(OutputParams & op) const
 {
+	// Passes the way to generate formulae to the XHTML output code.
+	// In particular, this function has no impact on the DocBook code, as it
+	// uses another mechanism to handle math flavours.
 	switch (params().html_math_output) {
 	case BufferParams::MathML:
 		op.math_flavor = OutputParams::MathAsMathML;
@@ -4057,6 +4476,8 @@ void Buffer::setMathFlavor(OutputParams & op) const
 Buffer::ExportStatus Buffer::doExport(string const & target, bool put_in_tempdir,
 	bool includeall, string & result_file) const
 {
+	if (removeBiblioTemps)
+		removeBiblioTempFiles();
 	LYXERR(Debug::FILES, "target=" << target);
 	OutputParams runparams(&params().encoding());
 	string format = target;
@@ -4065,27 +4486,28 @@ Buffer::ExportStatus Buffer::doExport(string const & target, bool put_in_tempdir
 	if (pos != string::npos) {
 		dest_filename = target.substr(pos + 1, target.length() - pos - 1);
 		format = target.substr(0, pos);
+		if (format == "default")
+			format = params().getDefaultOutputFormat();
 		runparams.export_folder = FileName(dest_filename).onlyPath().realPath();
 		FileName(dest_filename).onlyPath().createPath();
 		LYXERR(Debug::FILES, "format=" << format << ", dest_filename=" << dest_filename << ", export_folder=" << runparams.export_folder);
 	}
 	MarkAsExporting exporting(this);
 	string backend_format;
-	runparams.flavor = OutputParams::LATEX;
+	runparams.flavor = Flavor::LaTeX;
 	runparams.linelen = lyxrc.plaintext_linelen;
 	runparams.includeall = includeall;
 	vector<string> backs = params().backends();
 	Converters converters = theConverters();
 	bool need_nice_file = false;
 	if (find(backs.begin(), backs.end(), format) == backs.end()) {
-		// Get shortest path to format
+		// Get the shortest path to format
 		converters.buildGraph();
 		Graph::EdgePath path;
-		for (vector<string>::const_iterator it = backs.begin();
-		     it != backs.end(); ++it) {
-			Graph::EdgePath p = converters.getPath(*it, format);
+		for (string const & sit : backs) {
+			Graph::EdgePath p = converters.getPath(sit, format);
 			if (!p.empty() && (path.empty() || p.size() < path.size())) {
-				backend_format = *it;
+				backend_format = sit;
 				path = p;
 			}
 		}
@@ -4093,17 +4515,20 @@ Buffer::ExportStatus Buffer::doExport(string const & target, bool put_in_tempdir
 			if (!put_in_tempdir) {
 				// Only show this alert if this is an export to a non-temporary
 				// file (not for previewing).
-				Alert::error(_("Couldn't export file"), bformat(
-					_("No information for exporting the format %1$s."),
-					formats.prettyName(format)));
+				docstring s = bformat(_("No information for exporting the format %1$s."),
+						      translateIfPossible(theFormats().prettyName(format)));
+				if (format == "pdf4")
+					s += "\n"
+					  + bformat(_("Hint: use non-TeX fonts or set input encoding"
+						  " to '%1$s'"), from_utf8(encodings.fromLyXName("ascii")->guiName()));
+				Alert::error(_("Couldn't export file"), s);
 			}
 			return ExportNoPathToFormat;
 		}
 		runparams.flavor = converters.getFlavor(path, this);
-		Graph::EdgePath::const_iterator it = path.begin();
-		Graph::EdgePath::const_iterator en = path.end();
-		for (; it != en; ++it)
-			if (theConverters().get(*it).nice()) {
+		runparams.hyperref_driver = converters.getHyperrefDriver(path);
+		for (auto const & edge : path)
+			if (theConverters().get(edge).nice()) {
 				need_nice_file = true;
 				break;
 			}
@@ -4113,69 +4538,87 @@ Buffer::ExportStatus Buffer::doExport(string const & target, bool put_in_tempdir
 		LYXERR(Debug::FILES, "backend_format=" << backend_format);
 		// FIXME: Don't hardcode format names here, but use a flag
 		if (backend_format == "pdflatex")
-			runparams.flavor = OutputParams::PDFLATEX;
+			runparams.flavor = Flavor::PdfLaTeX;
 		else if (backend_format == "luatex")
-			runparams.flavor = OutputParams::LUATEX;
+			runparams.flavor = Flavor::LuaTeX;
 		else if (backend_format == "dviluatex")
-			runparams.flavor = OutputParams::DVILUATEX;
+			runparams.flavor = Flavor::DviLuaTeX;
 		else if (backend_format == "xetex")
-			runparams.flavor = OutputParams::XETEX;
+			runparams.flavor = Flavor::XeTeX;
 	}
 
 	string filename = latexName(false);
 	filename = addName(temppath(), filename);
 	filename = changeExtension(filename,
-				   formats.extension(backend_format));
+				   theFormats().extension(backend_format));
 	LYXERR(Debug::FILES, "filename=" << filename);
 
 	// Plain text backend
 	if (backend_format == "text") {
-		runparams.flavor = OutputParams::TEXT;
-		writePlaintextFile(*this, FileName(filename), runparams);
+		runparams.flavor = Flavor::Text;
+		try {
+			writePlaintextFile(*this, FileName(filename), runparams);
+		}
+		catch (ConversionException const &) { return ExportCancel; }
 	}
 	// HTML backend
 	else if (backend_format == "xhtml") {
-		runparams.flavor = OutputParams::HTML;
+		runparams.flavor = Flavor::Html;
 		setMathFlavor(runparams);
-		makeLyXHTMLFile(FileName(filename), runparams);
+		if (makeLyXHTMLFile(FileName(filename), runparams) == ExportKilled)
+			return ExportKilled;
 	} else if (backend_format == "lyx")
 		writeFile(FileName(filename));
-	// Docbook backend
-	else if (params().isDocBook()) {
-		runparams.nice = !put_in_tempdir;
-		makeDocBookFile(FileName(filename), runparams);
+	// DocBook backend
+	else if (backend_format == "docbook5") {
+		runparams.flavor = Flavor::DocBook5;
+		runparams.nice = false;
+		if (makeDocBookFile(FileName(filename), runparams) == ExportKilled)
+			return ExportKilled;
 	}
 	// LaTeX backend
 	else if (backend_format == format || need_nice_file) {
 		runparams.nice = true;
-		bool const success = makeLaTeXFile(FileName(filename), string(), runparams);
+		ExportStatus const retval =
+			makeLaTeXFile(FileName(filename), string(), runparams);
+		if (retval == ExportKilled)
+			return ExportKilled;
 		if (d->cloned_buffer_)
 			d->cloned_buffer_->d->errorLists["Export"] = d->errorLists["Export"];
-		if (!success)
-			return ExportError;
+		if (retval != ExportSuccess)
+			return retval;
 	} else if (!lyxrc.tex_allows_spaces
 		   && contains(filePath(), ' ')) {
 		Alert::error(_("File name error"),
-			   _("The directory path to the document cannot contain spaces."));
+			bformat(_("The directory path to the document\n%1$s\n"
+			    "contains spaces, but your TeX installation does "
+			    "not allow them. You should save the file to a directory "
+					"whose name does not contain spaces."), from_utf8(filePath())));
 		return ExportTexPathHasSpaces;
 	} else {
 		runparams.nice = false;
-		bool const success = makeLaTeXFile(
-			FileName(filename), filePath(), runparams);
+		ExportStatus const retval =
+			makeLaTeXFile(FileName(filename), filePath(), runparams);
+		if (retval == ExportKilled)
+			return ExportKilled;
 		if (d->cloned_buffer_)
 			d->cloned_buffer_->d->errorLists["Export"] = d->errorLists["Export"];
-		if (!success)
+		if (retval != ExportSuccess)
 			return ExportError;
 	}
 
 	string const error_type = (format == "program")
 		? "Build" : params().bufferFormat();
 	ErrorList & error_list = d->errorLists[error_type];
-	string const ext = formats.extension(format);
+	string const ext = theFormats().extension(format);
 	FileName const tmp_result_file(changeExtension(filename, ext));
-	bool const success = converters.convert(this, FileName(filename),
-		tmp_result_file, FileName(absFileName()), backend_format, format,
-		error_list);
+	Converters::RetVal const retval = 
+		converters.convert(this, FileName(filename), tmp_result_file,
+				   FileName(absFileName()), backend_format, format,
+				   error_list, Converters::none, includeall);
+	if (retval == Converters::KILLED)
+		return ExportCancel;
+	bool success = (retval == Converters::SUCCESS);
 
 	// Emit the signal to show the error list or copy it back to the
 	// cloned Buffer so that it can be emitted afterwards.
@@ -4188,21 +4631,19 @@ Buffer::ExportStatus Buffer::doExport(string const & target, bool put_in_tempdir
 		else
 			errors(error_type);
 		// also to the children, in case of master-buffer-view
-		ListOfBuffers clist = getDescendents();
-		ListOfBuffers::const_iterator cit = clist.begin();
-		ListOfBuffers::const_iterator const cen = clist.end();
-		for (; cit != cen; ++cit) {
+		ListOfBuffers clist = getDescendants();
+		for (auto const & bit : clist) {
 			if (runparams.silent)
-				(*cit)->d->errorLists[error_type].clear();
+				bit->d->errorLists[error_type].clear();
 			else if (d->cloned_buffer_) {
 				// Enable reverse search by copying back the
 				// texrow object to the cloned buffer.
 				// FIXME: this is not thread safe.
-				(*cit)->d->cloned_buffer_->d->texrow = (*cit)->d->texrow;
-				(*cit)->d->cloned_buffer_->d->errorLists[error_type] =
-					(*cit)->d->errorLists[error_type];
+				bit->d->cloned_buffer_->d->texrow = bit->d->texrow;
+				bit->d->cloned_buffer_->d->errorLists[error_type] =
+					bit->d->errorLists[error_type];
 			} else
-				(*cit)->errors(error_type, true);
+				bit->errors(error_type, true);
 		}
 	}
 
@@ -4212,8 +4653,8 @@ Buffer::ExportStatus Buffer::doExport(string const & target, bool put_in_tempdir
 		// FIXME: There is a possibility of concurrent access to texrow
 		// here from the main GUI thread that should be securized.
 		d->cloned_buffer_->d->texrow = d->texrow;
-		string const error_type = params().bufferFormat();
-		d->cloned_buffer_->d->errorLists[error_type] = d->errorLists[error_type];
+		string const err_type = params().bufferFormat();
+		d->cloned_buffer_->d->errorLists[error_type] = d->errorLists[err_type];
 	}
 
 
@@ -4226,9 +4667,9 @@ Buffer::ExportStatus Buffer::doExport(string const & target, bool put_in_tempdir
 		result_file = changeExtension(d->exportFileName().absFileName(), ext);
 	else
 		result_file = dest_filename;
-	// We need to copy referenced files (e. g. included graphics
+	// We need to copy referenced files (e.g. included graphics
 	// if format == "dvi") to the result dir.
-	vector<ExportedFile> const files =
+	vector<ExportedFile> const extfiles =
 		runparams.exportdata->externalFiles(format);
 	string const dest = runparams.export_folder.empty() ?
 		onlyPath(result_file) : runparams.export_folder;
@@ -4236,11 +4677,13 @@ Buffer::ExportStatus Buffer::doExport(string const & target, bool put_in_tempdir
 				 : force_overwrite == ALL_FILES;
 	CopyStatus status = use_force ? FORCE : SUCCESS;
 
-	vector<ExportedFile>::const_iterator it = files.begin();
-	vector<ExportedFile>::const_iterator const en = files.end();
-	for (; it != en && status != CANCEL; ++it) {
-		string const fmt = formats.getFormatFromFile(it->sourceName);
-		string fixedName = it->exportName;
+	for (ExportedFile const & exp : extfiles) {
+		if (status == CANCEL) {
+			message(_("Document export cancelled."));
+			return ExportCancel;
+		}
+		string const fmt = theFormats().getFormatFromFile(exp.sourceName);
+		string fixedName = exp.exportName;
 		if (!runparams.export_folder.empty()) {
 			// Relative pathnames starting with ../ will be sanitized
 			// if exporting to a different folder
@@ -4249,16 +4692,12 @@ Buffer::ExportStatus Buffer::doExport(string const & target, bool put_in_tempdir
 		}
 		FileName fixedFileName = makeAbsPath(fixedName, dest);
 		fixedFileName.onlyPath().createPath();
-		status = copyFile(fmt, it->sourceName,
+		status = copyFile(fmt, exp.sourceName,
 			fixedFileName,
-			it->exportName, status == FORCE,
+			exp.exportName, status == FORCE,
 			runparams.export_folder.empty());
 	}
 
-	if (status == CANCEL) {
-		message(_("Document export cancelled."));
-		return ExportCancel;
-	}
 
 	if (tmp_result_file.exists()) {
 		// Finally copy the main file
@@ -4275,13 +4714,13 @@ Buffer::ExportStatus Buffer::doExport(string const & target, bool put_in_tempdir
 		} else {
 			message(bformat(_("Document exported as %1$s "
 				"to file `%2$s'"),
-				formats.prettyName(format),
+				translateIfPossible(theFormats().prettyName(format)),
 				makeDisplayPath(result_file)));
 		}
 	} else {
 		// This must be a dummy converter like fax (bug 1888)
 		message(bformat(_("Document exported as %1$s"),
-			formats.prettyName(format)));
+			translateIfPossible(theFormats().prettyName(format))));
 	}
 
 	return success ? ExportSuccess : ExportConverterError;
@@ -4291,7 +4730,7 @@ Buffer::ExportStatus Buffer::doExport(string const & target, bool put_in_tempdir
 Buffer::ExportStatus Buffer::preview(string const & format) const
 {
 	bool const update_unincluded =
-			params().maintain_unincluded_children
+			params().maintain_unincluded_children != BufferParams::CM_None
 			&& !params().getIncludedChildren().empty();
 	return preview(format, update_unincluded);
 }
@@ -4314,13 +4753,13 @@ Buffer::ExportStatus Buffer::preview(string const & format, bool includeall) con
 	Impl * theimpl = isClone() ? d->cloned_buffer_->d : d;
 	theimpl->preview_file_ = previewFile;
 	theimpl->preview_format_ = format;
-	theimpl->preview_error_ = (status != ExportSuccess);
+	theimpl->require_fresh_start_ = (status != ExportSuccess);
 
 	if (status != ExportSuccess)
 		return status;
 
 	if (previewFile.exists())
-		return formats.view(*this, previewFile, format) ?
+		return theFormats().view(*this, previewFile, format) ?
 			PreviewSuccess : PreviewError;
 
 	// Successful export but no output file?
@@ -4353,7 +4792,7 @@ Buffer::ReadStatus Buffer::loadEmergency()
 		"%1$s exists.\n\nRecover emergency save?"), file);
 
 	int const load_emerg = Alert::prompt(_("Load emergency save?"), text,
-		0, 2, _("&Recover"), _("&Load Original"), _("&Cancel"));
+		0, 3, _("&Recover"), _("&Load Original"), _("&Only show difference"), _("&Cancel"));
 
 	switch (load_emerg)
 	{
@@ -4362,7 +4801,7 @@ Buffer::ReadStatus Buffer::loadEmergency()
 		ReadStatus const ret_llf = loadThisLyXFile(emergencyFile);
 		bool const success = (ret_llf == ReadSuccess);
 		if (success) {
-			if (isReadonly()) {
+			if (hasReadonlyFlag()) {
 				Alert::warning(_("File is read-only"),
 					bformat(_("An emergency file is successfully loaded, "
 					"but the original file %1$s is marked read-only. "
@@ -4395,9 +4834,55 @@ Buffer::ReadStatus Buffer::loadEmergency()
 				_("&Remove"), _("&Keep"));
 		if (del_emerg == 0)
 			emergencyFile.removeFile();
+		else {
+			// See bug #11464
+			FileName newname;
+			string const ename = emergencyFile.absFileName();
+			bool noname = true;
+			// Surely we can find one in 100 tries?
+			for (int i = 1; i < 100; ++i) {
+				newname.set(ename + to_string(i) + ".lyx");
+				if (!newname.exists()) {
+					noname = false;
+					break;
+				}
+			}
+			if (!noname) {
+				// renameTo returns true on success. So inverting that
+				// will give us true if we fail.
+				noname = !emergencyFile.renameTo(newname);
+			}
+			if (noname) {
+				Alert::warning(_("Can't rename emergency file!"),
+					_("LyX was unable to rename the emergency file. "
+					  "You should do so manually. Otherwise, you will be "
+					  "asked about it again the next time you try to load "
+					  "this file, and may over-write your own work."));
+			} else {
+				Alert::warning(_("Emergency File Renamed"),
+					bformat(_("Emergency file renamed as:\n %1$s"),
+					from_utf8(newname.onlyFileName())));
+			}
+		}
 		return ReadOriginal;
 	}
 
+	case 2: {
+		string const f1 = d->filename.absFileName();
+		string const f2 = emergencyFile.absFileName();
+		if (loadThisLyXFile(d->filename) != ReadSuccess)
+			return ReadCancel;
+		string const par = "compare run-blocking " + quoteName(f1) + " " + quoteName(f2);
+		LYXERR(Debug::FILES, par << "\n");
+		lyx::dispatch(FuncRequest(LFUN_DIALOG_SHOW, par));
+
+		//release the emergency buffer loaded by compare
+		Buffer * emerBuffer = theBufferList().getBuffer(emergencyFile);
+		if (emerBuffer)
+			theBufferList().release(emerBuffer);
+
+		return ReadCancel; //Release the buffer of Original immediatelly
+	}
 	default:
 		break;
 	}
@@ -4425,7 +4910,7 @@ Buffer::ReadStatus Buffer::loadAutosave()
 		ReadStatus const ret_llf = loadThisLyXFile(autosaveFile);
 		// the file is not saved if we load the autosave file.
 		if (ret_llf == ReadSuccess) {
-			if (isReadonly()) {
+			if (hasReadonlyFlag()) {
 				Alert::warning(_("File is read-only"),
 					bformat(_("A backup file is successfully loaded, "
 					"but the original file %1$s is marked read-only. "
@@ -4476,65 +4961,61 @@ Buffer::ReadStatus Buffer::loadThisLyXFile(FileName const & fn)
 }
 
 
-void Buffer::bufferErrors(TeXErrors const & terr, ErrorList & errorList) const
+void Buffer::Impl::traverseErrors(TeXErrors::Errors::const_iterator err, TeXErrors::Errors::const_iterator end, ErrorList & errorList) const
 {
-	TeXErrors::Errors::const_iterator it = terr.begin();
-	TeXErrors::Errors::const_iterator end = terr.end();
-	ListOfBuffers clist = getDescendents();
-	ListOfBuffers::const_iterator cen = clist.end();
-
-	for (; it != end; ++it) {
-		int id_start = -1;
-		int pos_start = -1;
-		int errorRow = it->error_in_line;
-		Buffer const * buf = 0;
-		Impl const * p = d;
-		if (it->child_name.empty())
-		    p->texrow.getIdFromRow(errorRow, id_start, pos_start);
+	for (; err != end; ++err) {
+		TexRow::TextEntry start = TexRow::text_none, end = TexRow::text_none;
+		int errorRow = err->error_in_line;
+		Buffer const * buf = nullptr;
+		Impl const * p = this;
+		if (err->child_name.empty())
+			tie(start, end) = p->texrow.getEntriesFromRow(errorRow);
 		else {
 			// The error occurred in a child
-			ListOfBuffers::const_iterator cit = clist.begin();
-			for (; cit != cen; ++cit) {
+			for (Buffer const * child : owner_->getDescendants()) {
 				string const child_name =
-					DocFileName(changeExtension(
-						(*cit)->absFileName(), "tex")).
-							mangledFileName();
-				if (it->child_name != child_name)
+					DocFileName(changeExtension(child->absFileName(), "tex")).
+					mangledFileName();
+				if (err->child_name != child_name)
 					continue;
-				(*cit)->d->texrow.getIdFromRow(errorRow,
-							id_start, pos_start);
-				if (id_start != -1) {
-					buf = d->cloned_buffer_
-						? (*cit)->d->cloned_buffer_->d->owner_
-						: (*cit)->d->owner_;
-					p = (*cit)->d;
+				tie(start, end) = child->d->texrow.getEntriesFromRow(errorRow);
+				if (!TexRow::isNone(start)) {
+					buf = this->cloned_buffer_
+						? child->d->cloned_buffer_->d->owner_
+						: child->d->owner_;
+					p = child->d;
 					break;
 				}
 			}
 		}
-		int id_end = -1;
-		int pos_end = -1;
-		bool found;
-		do {
-			++errorRow;
-			found = p->texrow.getIdFromRow(errorRow, id_end, pos_end);
-		} while (found && id_start == id_end && pos_start == pos_end);
-
-		if (id_start != id_end) {
-			// Next registered position is outside the inset where
-			// the error occurred, so signal end-of-paragraph
-			pos_end = 0;
-		}
-
-		errorList.push_back(ErrorItem(it->error_desc,
-			it->error_text, id_start, pos_start, pos_end, buf));
+		errorList.push_back(ErrorItem(err->error_desc, err->error_text,
+		                              start, end, buf));
 	}
 }
 
 
-void Buffer::setBuffersForInsets() const
+void Buffer::bufferErrors(TeXErrors const & terr, ErrorList & errorList) const
+{
+	TeXErrors::Errors::const_iterator err = terr.begin();
+	TeXErrors::Errors::const_iterator end = terr.end();
+
+	d->traverseErrors(err, end, errorList);
+}
+
+
+void Buffer::bufferRefs(TeXErrors const & terr, ErrorList & errorList) const
+{
+	TeXErrors::Errors::const_iterator err = terr.begin_ref();
+	TeXErrors::Errors::const_iterator end = terr.end_ref();
+
+	d->traverseErrors(err, end, errorList);
+}
+
+
+void Buffer::updateBuffer() const
 {
-	inset().setBuffer(const_cast<Buffer &>(*this));
+	updateBuffer(UpdateMaster, InternalUpdate);
+	d->need_update = false;
 }
 
 
@@ -4542,14 +5023,25 @@ void Buffer::updateBuffer(UpdateScope scope, UpdateType utype) const
 {
 	LBUFERR(!text().paragraphs().empty());
 
+	// This can be called when loading a file, so that there be no
+	// open undo group.
+	UndoGroupHelper ugh(const_cast<Buffer *>(this));
+
 	// Use the master text class also for child documents
 	Buffer const * const master = masterBuffer();
 	DocumentClass const & textclass = master->params().documentClass();
 
-	// do this only if we are the top-level Buffer
-	if (master == this) {
+	docstring_list old_bibfiles;
+	// Do this only if we are the top-level Buffer. We also need to account
+	// for the case of a previewed child with ignored parent here.
+	if (master == this && !d->ignore_parent) {
 		textclass.counters().reset(from_ascii("bibitem"));
 		reloadBibInfoCache();
+		// we will re-read this cache as we go through, but we need
+		// to know whether it's changed to know whether we need to
+		// update the bibinfo cache.
+		old_bibfiles = d->bibfiles_cache_;
+		d->bibfiles_cache_.clear();
 	}
 
 	// keep the buffers to be children in this set. If the call from the
@@ -4565,7 +5057,7 @@ void Buffer::updateBuffer(UpdateScope scope, UpdateType utype) const
 			// not updated during the updateBuffer call and TocModel::toc_ is invalid
 			// (bug 5699). The same happens if the master buffer is open in a different
 			// window. This test catches both possibilities.
-			// See: http://marc.info/?l=lyx-devel&m=138590578911716&w=2
+			// See: https://marc.info/?l=lyx-devel&m=138590578911716&w=2
 			// There remains a problem here: If there is another child open in yet a third
 			// window, that TOC is not updated. So some more general solution is needed at
 			// some point.
@@ -4587,24 +5079,65 @@ void Buffer::updateBuffer(UpdateScope scope, UpdateType utype) const
 	// update all caches
 	clearReferenceCache();
 	updateMacros();
-	setChangesPresent(false);
 
 	Buffer & cbuf = const_cast<Buffer &>(*this);
+	// if we are reloading, then we could have a dangling TOC,
+	// in effect. so we need to go ahead and reset, even though
+	// we will do so again when we rebuild the TOC later.
+	cbuf.tocBackend().reset();
 
 	// do the real work
 	ParIterator parit = cbuf.par_iterator_begin();
+	if (scope == UpdateMaster)
+		clearIncludeList();
 	updateBuffer(parit, utype);
 
+	// If this document has siblings, then update the TocBackend later. The
+	// reason is to ensure that later siblings are up to date when e.g. the
+	// broken or not status of references is computed. The update is called
+	// in InsetInclude::addToToc.
 	if (master != this)
-		// TocBackend update will be done later.
 		return;
 
-	d->bibinfo_cache_valid_ = true;
+	// if the bibfiles changed, the cache of bibinfo is invalid
+	docstring_list new_bibfiles = d->bibfiles_cache_;
+	// this is a trick to determine whether the two vectors have
+	// the same elements.
+	sort(new_bibfiles.begin(), new_bibfiles.end());
+	sort(old_bibfiles.begin(), old_bibfiles.end());
+	if (old_bibfiles != new_bibfiles) {
+		LYXERR(Debug::FILES, "Reloading bibinfo cache.");
+		invalidateBibinfoCache();
+		reloadBibInfoCache();
+		// We relied upon the bibinfo cache when recalculating labels. But that
+		// cache was invalid, although we didn't find that out until now. So we
+		// have to do it all again.
+		// That said, the only thing we really need to do is update the citation
+		// labels. Nothing else will have changed. So we could create a new 
+		// UpdateType that would signal that fact, if we needed to do so.
+		parit = cbuf.par_iterator_begin();
+		// we will be re-doing the counters and references and such.
+		textclass.counters().reset();
+		clearReferenceCache();
+		// we should not need to do this again?
+		// updateMacros();
+		updateBuffer(parit, utype);
+		// this will already have been done by reloadBibInfoCache();
+		// d->bibinfo_cache_valid_ = true;
+	}
+	else {
+		LYXERR(Debug::FILES, "Bibfiles unchanged.");
+		// this is also set to true on the other path, by reloadBibInfoCache.
+		d->bibinfo_cache_valid_ = true;
+	}
 	d->cite_labels_valid_ = true;
 	/// FIXME: Perf
+	clearIncludeList();
 	cbuf.tocBackend().update(true, utype);
 	if (scope == UpdateMaster)
 		cbuf.structureChanged();
+
+	d->need_update = false;
 }
 
 
@@ -4675,7 +5208,7 @@ static bool needEnumCounterReset(ParIterator const & it)
 		--prev_it.top().pit();
 		Paragraph const & prev_par = *prev_it;
 		if (prev_par.getDepth() <= cur_depth)
-			return  prev_par.layout().labeltype != LABEL_ENUMERATE;
+			return prev_par.layout().name() != par.layout().name();
 	}
 	// start of nested inset: reset
 	return true;
@@ -4716,27 +5249,11 @@ void Buffer::Impl::setLabel(ParIterator & it, UpdateType utype) const
 
 	switch(layout.labeltype) {
 	case LABEL_ITEMIZE: {
-		// At some point of time we should do something more
-		// clever here, like:
-		//   par.params().labelString(
-		//    bp.user_defined_bullet(par.itemdepth).getText());
-		// for now, use a simple hardcoded label
-		docstring itemlabel;
-		switch (par.itemdepth) {
-		case 0:
-			itemlabel = char_type(0x2022);
-			break;
-		case 1:
-			itemlabel = char_type(0x2013);
-			break;
-		case 2:
-			itemlabel = char_type(0x2217);
-			break;
-		case 3:
-			itemlabel = char_type(0x2219); // or 0x00b7
-			break;
-		}
-		par.params().labelString(itemlabel);
+		par.params().labelString(
+			(par.itemdepth < 4)
+					? bp.user_defined_bullet(par.itemdepth).getLabel()
+					  // Display fallback for too deeply nested items
+					: bformat(from_ascii("[?%1$d]"), int(par.itemdepth + 1)));
 		break;
 	}
 
@@ -4746,8 +5263,10 @@ void Buffer::Impl::setLabel(ParIterator & it, UpdateType utype) const
 		switch (par.itemdepth) {
 		case 2:
 			enumcounter += 'i';
+			// fall through
 		case 1:
 			enumcounter += 'i';
+			// fall through
 		case 0:
 			enumcounter += 'i';
 			break;
@@ -4759,9 +5278,14 @@ void Buffer::Impl::setLabel(ParIterator & it, UpdateType utype) const
 			break;
 		}
 
-		// Maybe we have to reset the enumeration counter.
-		if (needEnumCounterReset(it))
-			counters.reset(enumcounter);
+		if (needEnumCounterReset(it)) {
+			// Increase the parent counter?
+			if (layout.stepparentcounter)
+				counters.stepParent(enumcounter, utype);
+			// Maybe we have to reset the enumeration counter.
+			if (!layout.resumecounter)
+				counters.reset(enumcounter);
+		}
 		counters.step(enumcounter, utype);
 
 		string const & lang = par.getParLanguage(bp)->code();
@@ -4819,8 +5343,13 @@ void Buffer::Impl::setLabel(ParIterator & it, UpdateType utype) const
 }
 
 
-void Buffer::updateBuffer(ParIterator & parit, UpdateType utype) const
+void Buffer::updateBuffer(ParIterator & parit, UpdateType utype, bool const deleted) const
 {
+	// if fomatted references are shown in workarea update buffer accordingly
+	if (params().use_formatted_ref)
+		utype = OutputUpdate;
+
+	pushIncludedBuffer(this);
 	// LASSERT: Is it safe to continue here, or should we just return?
 	LASSERT(parit.pit() == 0, /**/);
 
@@ -4830,6 +5359,7 @@ void Buffer::updateBuffer(ParIterator & parit, UpdateType utype) const
 
 	depth_type maxdepth = 0;
 	pit_type const lastpit = parit.lastpit();
+	bool changed = false;
 	for ( ; parit.pit() <= lastpit ; ++parit.pit()) {
 		// reduce depth if necessary
 		if (parit->params().depth() > maxdepth) {
@@ -4840,7 +5370,7 @@ void Buffer::updateBuffer(ParIterator & parit, UpdateType utype) const
 			 * non-const. This would however be costly in
 			 * terms of code duplication.
 			 */
-			const_cast<Buffer *>(this)->undo().recordUndo(CursorData(parit));
+			CursorData(parit).recordUndo();
 			parit->params().depth(maxdepth);
 		}
 		maxdepth = parit->getMaxDepthAfter();
@@ -4856,17 +5386,33 @@ void Buffer::updateBuffer(ParIterator & parit, UpdateType utype) const
 		// set the counter for this paragraph
 		d->setLabel(parit, utype);
 
-		// update change-tracking flag 
-		parit->addChangesToBuffer(*this);
-
 		// now the insets
-		InsetList::const_iterator iit = parit->insetList().begin();
-		InsetList::const_iterator end = parit->insetList().end();
-		for (; iit != end; ++iit) {
-			parit.pos() = iit->pos;
-			iit->inset->updateBuffer(parit, utype);
+		for (auto const & insit : parit->insetList()) {
+			parit.pos() = insit.pos;
+			insit.inset->updateBuffer(parit, utype, deleted || parit->isDeleted(insit.pos));
+			changed |= insit.inset->isChanged();
 		}
+
+		// are there changes in this paragraph?
+		changed |= parit->isChanged();
 	}
+
+	// set change indicator for the inset (or the cell that the iterator
+	// points to, if applicable).
+	parit.text()->inset().isChanged(changed);
+	popIncludedBuffer();
+}
+
+
+void Buffer::forceUpdate() const
+{
+	d->need_update = true;
+}
+
+
+bool Buffer::needUpdate() const
+{
+	return d->need_update;
 }
 
 
@@ -4908,6 +5454,15 @@ int Buffer::spellCheck(DocIterator & from, DocIterator & to,
 }
 
 
+void Buffer::requestSpellcheck()
+{
+	ParagraphList::iterator pit = paragraphs().begin();
+	ParagraphList::iterator pend = paragraphs().end();
+	for (; pit != pend; ++pit)
+		pit->requestSpellCheck();
+}
+
+
 void Buffer::Impl::updateStatistics(DocIterator & from, DocIterator & to, bool skipNoOutput)
 {
 	bool inword = false;
@@ -4943,10 +5498,19 @@ void Buffer::Impl::updateStatistics(DocIterator & from, DocIterator & to, bool s
 					++word_count_;
 					inword = true;
 				}
-				if (ins && ins->isLetter())
-					++char_count_;
+				if (ins && ins->isLetter()) {
+					odocstringstream os;
+					ins->toString(os);
+					char_count_ += os.str().length();
+				}
 				else if (ins && ins->isSpace())
 					++blank_count_;
+				else if (ins) {
+					pair<int, int> words = ins->isWords();
+					char_count_ += words.first;
+					word_count_ += words.second;
+					inword = false;
+				}
 				else {
 					char_type const c = par.getChar(pos);
 					if (isPrintableNonspace(c))
@@ -4979,22 +5543,38 @@ int Buffer::charCount(bool with_blanks) const
 }
 
 
+bool Buffer::areChangesPresent() const
+{
+	return inset().isChanged();
+}
+
+
 Buffer::ReadStatus Buffer::reload()
 {
 	setBusy(true);
-	// c.f. bug http://www.lyx.org/trac/ticket/6587
+	// c.f. bug https://www.lyx.org/trac/ticket/6587
 	removeAutosaveFile();
 	// e.g., read-only status could have changed due to version control
 	d->filename.refresh();
 	docstring const disp_fn = makeDisplayPath(d->filename.absFileName());
 
 	// clear parent. this will get reset if need be.
-	d->setParent(0);
+	Buffer const * oldparent = d->parent();
+	d->setParent(nullptr);
 	ReadStatus const status = loadLyXFile();
+	// The inset members in cursors held by buffer views are now wrong.
+	workAreaManager().sanitizeCursors();
+	setBusy(false);
 	if (status == ReadSuccess) {
 		updateBuffer();
 		changed(true);
 		updateTitles();
+		// reset parent if this hasn't been done yet
+		// but only if this is still its child (e.g.,
+		// not after the former child has been saved as...) 
+		if (!d->parent() && oldparent && oldparent->isFullyLoaded()
+		    && oldparent->isChild(this))
+			d->setParent(oldparent);
 		markClean();
 		message(bformat(_("Document %1$s reloaded."), disp_fn));
 		d->undo_.clear();
@@ -5048,11 +5628,9 @@ bool Buffer::saveAs(FileName const & fn)
 
 void Buffer::checkChildBuffers()
 {
-	Impl::BufferPositionMap::iterator it = d->children_positions.begin();
-	Impl::BufferPositionMap::iterator const en = d->children_positions.end();
-	for (; it != en; ++it) {
-		DocIterator dit = it->second;
-		Buffer * cbuf = const_cast<Buffer *>(it->first);
+	for (auto const & bit : d->children_positions) {
+		DocIterator dit = bit.second;
+		Buffer * cbuf = const_cast<Buffer *>(bit.first);
 		if (!cbuf || !theBufferList().isLoaded(cbuf))
 			continue;
 		Inset * inset = dit.nextInset();
@@ -5065,8 +5643,8 @@ void Buffer::checkChildBuffers()
 		if (oldloc == newloc)
 			continue;
 		// the location of the child file is incorrect.
-		cbuf->setParent(0);
-		inset_inc->setChildBuffer(0);
+		cbuf->setParent(nullptr);
+		inset_inc->setChildBuffer(nullptr);
 	}
 	// invalidate cache of children
 	d->children_positions.clear();
@@ -5091,7 +5669,7 @@ void Buffer::checkMasterBuffer()
 	if (master->isChild(this))
 		setParent(master);
 	else
-		setParent(0);
+		setParent(nullptr);
 }
 
 
@@ -5124,28 +5702,119 @@ string Buffer::includedFilePath(string const & name, string const & ext) const
 }
 
 
-void Buffer::setChangesPresent(bool b) const
+void Buffer::Impl::refreshFileMonitor()
 {
-	d->tracked_changes_present_ = b;
+	if (file_monitor_ && file_monitor_->filename() == filename.absFileName()) {
+		file_monitor_->refresh();
+		return;
+	}
+
+	// The previous file monitor is invalid
+	// This also destroys the previous file monitor and all its connections
+	file_monitor_ = FileSystemWatcher::monitor(filename);
+	// file_monitor_ will be destroyed with *this, so it is not going to call a
+	// destroyed object method.
+	file_monitor_->connect([this](bool exists) {
+			fileExternallyModified(exists);
+		});
 }
 
 
-bool Buffer::areChangesPresent() const
+void Buffer::Impl::fileExternallyModified(bool const exists)
 {
-	return d->tracked_changes_present_;
+	// ignore notifications after our own saving operations
+	if (checksum_ == filename.checksum()) {
+		LYXERR(Debug::FILES, "External modification but "
+		       "checksum unchanged: " << filename);
+		return;
+	}
+	lyx_clean = false;
+	// If the file has been deleted, only mark the file as dirty since it is
+	// pointless to prompt for reloading. If later a file is moved into this
+	// location, then the externally modified warning will appear then.
+	if (exists)
+		externally_modified_ = true;
+	// Update external modification notification.
+	// Dirty buffers must be visible at all times.
+	if (wa_ && wa_->unhide(owner_)) {
+		wa_->updateTitles();
+		if (!exists) {
+			frontend::Alert::warning(
+				_("File deleted from disk"),
+				bformat(_("The file\n  %1$s\n"
+					   "has been deleted from disk!"),
+					from_utf8(filename.absFileName())));
+		}
+	}
+	else
+		// Unable to unhide the buffer (e.g. no GUI or not current View)
+		lyx_clean = true;
+}
+
+
+bool Buffer::notifiesExternalModification() const
+{
+	return d->externally_modified_;
+}
+
+
+void Buffer::clearExternalModification() const
+{
+	d->externally_modified_ = false;
+	if (d->wa_)
+		d->wa_->updateTitles();
+}
+
+
+void Buffer::pushIncludedBuffer(Buffer const * buf) const
+{
+	masterBuffer()->d->include_list_.push_back(buf);
+	if (lyxerr.debugging(Debug::FILES)) {
+		LYXERR0("Pushed. Stack now:");
+		if (masterBuffer()->d->include_list_.empty())
+			LYXERR0("EMPTY!");
+		else
+			for (auto const & b : masterBuffer()->d->include_list_)
+				LYXERR0(b->fileName());
+	}
+}
+
+
+void Buffer::popIncludedBuffer() const
+{
+	masterBuffer()->d->include_list_.pop_back();
+	if (lyxerr.debugging(Debug::FILES)) {
+		LYXERR0("Popped. Stack now:");
+		if (masterBuffer()->d->include_list_.empty())
+			LYXERR0("EMPTY!");
+		else
+			for (auto const & b : masterBuffer()->d->include_list_)
+				LYXERR0(b->fileName());
+	}
 }
 
 
-void Buffer::updateChangesPresent() const
+bool Buffer::isBufferIncluded(Buffer const * buf) const
 {
-	LYXERR(Debug::CHANGES, "Buffer::updateChangesPresent");
-	setChangesPresent(false);
-	ParConstIterator it = par_iterator_begin();
-	ParConstIterator const end = par_iterator_end();
-	for (; !areChangesPresent() && it != end; ++it)
-		it->addChangesToBuffer(*this);
+	if (!buf)
+		return false;
+	if (lyxerr.debugging(Debug::FILES)) {
+		LYXERR0("Checking for " << buf->fileName() << ". Stack now:");
+		if (masterBuffer()->d->include_list_.empty())
+			LYXERR0("EMPTY!");
+		else
+			for (auto const & b : masterBuffer()->d->include_list_)
+				LYXERR0(b->fileName());
+	}
+	list<Buffer const *> const & blist = masterBuffer()->d->include_list_;
+	return find(blist.begin(), blist.end(), buf) != blist.end();
 }
 
 
+void Buffer::clearIncludeList() const
+{
+	LYXERR(Debug::FILES, "Clearing include list for " << fileName());
+	d->include_list_.clear();
+}
 
 } // namespace lyx